diff --git a/src/main/resources/update/gitbucket-core_4.24.xml b/src/main/resources/update/gitbucket-core_4.24.xml
new file mode 100644
index 0000000..03249f5
--- /dev/null
+++ b/src/main/resources/update/gitbucket-core_4.24.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<changeSet>
+  <createTable tableName="ACCOUNT_EXTRA_MAIL_ADDRESS">
+    <column name="USER_NAME" type="varchar(100)" nullable="false"/>
+    <column name="EXTRA_MAIL_ADDRESS" type="varchar(100)" nullable="false"/>
+  </createTable>
+
+  <addPrimaryKey constraintName="IDX_ACCOUNT_EXTRA_MAIL_ADDRESS_PK" tableName="ACCOUNT_EXTRA_MAIL_ADDRESS" columnNames="USER_NAME, EXTRA_MAIL_ADDRESS"/>
+  <addUniqueConstraint constraintName="IDX_ACCOUNT_EXTRA_MAIL_ADDRESS_1" tableName="ACCOUNT_EXTRA_MAIL_ADDRESS" columnNames="EXTRA_MAIL_ADDRESS"/>
+</changeSet>
diff --git a/src/main/scala/gitbucket/core/GitBucketCoreModule.scala b/src/main/scala/gitbucket/core/GitBucketCoreModule.scala
index bcca992..8b58e07 100644
--- a/src/main/scala/gitbucket/core/GitBucketCoreModule.scala
+++ b/src/main/scala/gitbucket/core/GitBucketCoreModule.scala
@@ -51,5 +51,6 @@
       new Version("4.21.2"),
       new Version("4.22.0", new LiquibaseMigration("update/gitbucket-core_4.22.xml")),
       new Version("4.23.0", new LiquibaseMigration("update/gitbucket-core_4.23.xml")),
-      new Version("4.23.1")
+      new Version("4.23.1"),
+      new Version("4.24.0", new LiquibaseMigration("update/gitbucket-core_4.24.xml"))
     )
diff --git a/src/main/scala/gitbucket/core/controller/AccountController.scala b/src/main/scala/gitbucket/core/controller/AccountController.scala
index 6223eb5..3f12900 100644
--- a/src/main/scala/gitbucket/core/controller/AccountController.scala
+++ b/src/main/scala/gitbucket/core/controller/AccountController.scala
@@ -2,7 +2,7 @@
 
 import gitbucket.core.account.html
 import gitbucket.core.helper
-import gitbucket.core.model.{AccountWebHook, GroupMember, RepositoryWebHook, Role, WebHook, WebHookContentType}
+import gitbucket.core.model._
 import gitbucket.core.plugin.PluginRegistry
 import gitbucket.core.service._
 import gitbucket.core.service.WebHookService._
@@ -54,6 +54,7 @@
     password: String,
     fullName: String,
     mailAddress: String,
+    extraMailAddresses: List[String],
     description: Option[String],
     url: Option[String],
     fileId: Option[String]
@@ -63,6 +64,7 @@
     password: Option[String],
     fullName: String,
     mailAddress: String,
+    extraMailAddresses: List[String],
     description: Option[String],
     url: Option[String],
     fileId: Option[String],
@@ -78,6 +80,9 @@
     "password" -> trim(label("Password", text(required, maxlength(20), password))),
     "fullName" -> trim(label("Full Name", text(required, maxlength(100)))),
     "mailAddress" -> trim(label("Mail Address", text(required, maxlength(100), uniqueMailAddress()))),
+    "extraMailAddresses" -> list(
+      trim(label("Additional Mail Address", text(maxlength(100), uniqueExtraMailAddress())))
+    ),
     "description" -> trim(label("bio", optional(text()))),
     "url" -> trim(label("URL", optional(text(maxlength(200))))),
     "fileId" -> trim(label("File ID", optional(text())))
@@ -87,6 +92,9 @@
     "password" -> trim(label("Password", optional(text(maxlength(20), password)))),
     "fullName" -> trim(label("Full Name", text(required, maxlength(100)))),
     "mailAddress" -> trim(label("Mail Address", text(required, maxlength(100), uniqueMailAddress("userName")))),
+    "extraMailAddresses" -> list(
+      trim(label("Additional Mail Address", text(maxlength(100), uniqueExtraMailAddress("userName"))))
+    ),
     "description" -> trim(label("bio", optional(text()))),
     "url" -> trim(label("URL", optional(text(maxlength(200))))),
     "fileId" -> trim(label("File ID", optional(text()))),
@@ -295,26 +303,29 @@
   get("/:userName/_edit")(oneselfOnly {
     val userName = params("userName")
     getAccountByUserName(userName).map { x =>
-      html.edit(x, flash.get("info"), flash.get("error"))
+      val extraMails = getAccountExtraMailAddresses(userName)
+      html.edit(x, extraMails, flash.get("info"), flash.get("error"))
     } getOrElse NotFound()
   })
 
   post("/:userName/_edit", editForm)(oneselfOnly { form =>
     val userName = params("userName")
-    getAccountByUserName(userName).map { account =>
-      updateAccount(
-        account.copy(
-          password = form.password.map(sha1).getOrElse(account.password),
-          fullName = form.fullName,
-          mailAddress = form.mailAddress,
-          description = form.description,
-          url = form.url
+    getAccountByUserName(userName).map {
+      account =>
+        updateAccount(
+          account.copy(
+            password = form.password.map(sha1).getOrElse(account.password),
+            fullName = form.fullName,
+            mailAddress = form.mailAddress,
+            description = form.description,
+            url = form.url
+          )
         )
-      )
 
-      updateImage(userName, form.fileId, form.clearImage)
-      flash += "info" -> "Account information has been updated."
-      redirect(s"/${userName}/_edit")
+        updateImage(userName, form.fileId, form.clearImage)
+        updateAccountExtraMailAddresses(userName, form.extraMailAddresses.filter(_ != ""))
+        flash += "info" -> "Account information has been updated."
+        redirect(s"/${userName}/_edit")
 
     } getOrElse NotFound()
   })
@@ -552,6 +563,7 @@
         form.url
       )
       updateImage(form.userName, form.fileId, false)
+      updateAccountExtraMailAddresses(form.userName, form.extraMailAddresses)
       redirect("/signin")
     } else NotFound()
   }
diff --git a/src/main/scala/gitbucket/core/controller/ControllerBase.scala b/src/main/scala/gitbucket/core/controller/ControllerBase.scala
index a2310b3..b80fa1e 100644
--- a/src/main/scala/gitbucket/core/controller/ControllerBase.scala
+++ b/src/main/scala/gitbucket/core/controller/ControllerBase.scala
@@ -359,13 +359,42 @@
       params: Map[String, Seq[String]],
       messages: Messages
     ): Option[String] = {
-      getAccountByMailAddress(value, true)
-        .filter { x =>
-          if (paramName.isEmpty) true else Some(x.userName) != params.optionValue(paramName)
-        }
-        .map { _ =>
-          "Mail address is already registered."
-        }
+      val extraMailAddresses = params.filterKeys(k => k.startsWith("extraMailAddresses"))
+      if (extraMailAddresses.exists {
+            case (k, v) =>
+              v.contains(value)
+          }) {
+        Some("These mail addresses are duplicated.")
+      } else {
+        getAccountByMailAddress(value, true)
+          .collect {
+            case x if paramName.isEmpty || Some(x.userName) != params.optionValue(paramName) =>
+              "Mail address is already registered."
+          }
+      }
+    }
+  }
+
+  protected def uniqueExtraMailAddress(paramName: String = ""): Constraint = new Constraint() {
+    override def validate(
+      name: String,
+      value: String,
+      params: Map[String, Seq[String]],
+      messages: Messages
+    ): Option[String] = {
+      val extraMailAddresses = params.filterKeys(k => k.startsWith("extraMailAddresses"))
+      if (Some(value) == params.optionValue("mailAddress") || extraMailAddresses.count {
+            case (k, v) =>
+              v.contains(value)
+          } > 1) {
+        Some("These mail addresses are duplicated.")
+      } else {
+        getAccountByMailAddress(value, true)
+          .collect {
+            case x if paramName.isEmpty || Some(x.userName) != params.optionValue(paramName) =>
+              "Mail address is already registered."
+          }
+      }
     }
   }
 
diff --git a/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala b/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
index d2d0649..513affc 100644
--- a/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
+++ b/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
@@ -124,6 +124,7 @@
     password: String,
     fullName: String,
     mailAddress: String,
+    extraMailAddresses: List[String],
     isAdmin: Boolean,
     description: Option[String],
     url: Option[String],
@@ -135,6 +136,7 @@
     password: Option[String],
     fullName: String,
     mailAddress: String,
+    extraMailAddresses: List[String],
     isAdmin: Boolean,
     description: Option[String],
     url: Option[String],
@@ -166,6 +168,9 @@
     "password" -> trim(label("Password", text(required, maxlength(20), password))),
     "fullName" -> trim(label("Full Name", text(required, maxlength(100)))),
     "mailAddress" -> trim(label("Mail Address", text(required, maxlength(100), uniqueMailAddress()))),
+    "extraMailAddresses" -> list(
+      trim(label("Additional Mail Address", text(maxlength(100), uniqueExtraMailAddress("userName"))))
+    ),
     "isAdmin" -> trim(label("User Type", boolean())),
     "description" -> trim(label("bio", optional(text()))),
     "url" -> trim(label("URL", optional(text(maxlength(200))))),
@@ -177,6 +182,9 @@
     "password" -> trim(label("Password", optional(text(maxlength(20), password)))),
     "fullName" -> trim(label("Full Name", text(required, maxlength(100)))),
     "mailAddress" -> trim(label("Mail Address", text(required, maxlength(100), uniqueMailAddress("userName")))),
+    "extraMailAddresses" -> list(
+      trim(label("Additional Mail Address", text(maxlength(100), uniqueExtraMailAddress("userName"))))
+    ),
     "isAdmin" -> trim(label("User Type", boolean())),
     "description" -> trim(label("bio", optional(text()))),
     "url" -> trim(label("URL", optional(text(maxlength(200))))),
@@ -400,7 +408,7 @@
   })
 
   get("/admin/users/_newuser")(adminOnly {
-    html.user(None)
+    html.user(None, Nil)
   })
 
   post("/admin/users/_newuser", newUserForm)(adminOnly { form =>
@@ -414,12 +422,14 @@
       form.url
     )
     updateImage(form.userName, form.fileId, false)
+    updateAccountExtraMailAddresses(form.userName, form.extraMailAddresses.filter(_ != ""))
     redirect("/admin/users")
   })
 
   get("/admin/users/:userName/_edituser")(adminOnly {
     val userName = params("userName")
-    html.user(getAccountByUserName(userName, true), flash.get("error"))
+    val extraMails = getAccountExtraMailAddresses(userName)
+    html.user(getAccountByUserName(userName, true), extraMails, flash.get("error"))
   })
 
   post("/admin/users/:name/_edituser", editUserForm)(adminOnly { form =>
@@ -455,6 +465,7 @@
           )
 
           updateImage(userName, form.fileId, form.clearImage)
+          updateAccountExtraMailAddresses(userName, form.extraMailAddresses.filter(_ != ""))
 
           // call hooks
           if (form.isRemoved) PluginRegistry().getAccountHooks.foreach(_.deleted(userName))
diff --git a/src/main/scala/gitbucket/core/model/AccountExtraMailAddress.scala b/src/main/scala/gitbucket/core/model/AccountExtraMailAddress.scala
new file mode 100644
index 0000000..88cc2fe
--- /dev/null
+++ b/src/main/scala/gitbucket/core/model/AccountExtraMailAddress.scala
@@ -0,0 +1,19 @@
+package gitbucket.core.model
+
+trait AccountExtraMailAddressComponent { self: Profile =>
+  import profile.api._
+
+  lazy val AccountExtraMailAddresses = TableQuery[AccountExtraMailAddresses]
+
+  class AccountExtraMailAddresses(tag: Tag) extends Table[AccountExtraMailAddress](tag, "ACCOUNT_EXTRA_MAIL_ADDRESS") {
+    val userName = column[String]("USER_NAME", O PrimaryKey)
+    val extraMailAddress = column[String]("EXTRA_MAIL_ADDRESS", O PrimaryKey)
+    def * =
+      (userName, extraMailAddress) <> (AccountExtraMailAddress.tupled, AccountExtraMailAddress.unapply)
+  }
+}
+
+case class AccountExtraMailAddress(
+  userName: String,
+  extraMailAddress: String
+)
diff --git a/src/main/scala/gitbucket/core/model/Profile.scala b/src/main/scala/gitbucket/core/model/Profile.scala
index f35dec9..577c3ee 100644
--- a/src/main/scala/gitbucket/core/model/Profile.scala
+++ b/src/main/scala/gitbucket/core/model/Profile.scala
@@ -68,5 +68,6 @@
     with DeployKeyComponent
     with ReleaseTagComponent
     with ReleaseAssetComponent
+    with AccountExtraMailAddressComponent
 
 object Profile extends CoreProfile
diff --git a/src/main/scala/gitbucket/core/service/AccountService.scala b/src/main/scala/gitbucket/core/service/AccountService.scala
index 65c7ae0..8f0ba63 100644
--- a/src/main/scala/gitbucket/core/service/AccountService.scala
+++ b/src/main/scala/gitbucket/core/service/AccountService.scala
@@ -1,11 +1,11 @@
 package gitbucket.core.service
 
 import org.slf4j.LoggerFactory
-import gitbucket.core.model.{GroupMember, Account}
+import gitbucket.core.model.{Account, AccountExtraMailAddress, GroupMember}
 import gitbucket.core.model.Profile._
 import gitbucket.core.model.Profile.profile.blockingApi._
 import gitbucket.core.model.Profile.dateColumnType
-import gitbucket.core.util.{StringUtil, LDAPUtil}
+import gitbucket.core.util.{LDAPUtil, StringUtil}
 import StringUtil._
 import gitbucket.core.service.SystemSettingsService.SystemSettings
 
@@ -121,9 +121,16 @@
   def getAccountByMailAddress(mailAddress: String, includeRemoved: Boolean = false)(
     implicit s: Session
   ): Option[Account] =
-    Accounts filter (
-      t => (t.mailAddress.toLowerCase === mailAddress.toLowerCase.bind) && (t.removed === false.bind, !includeRemoved)
-    ) firstOption
+    (Accounts joinLeft AccountExtraMailAddresses on { case (a, e) => a.userName === e.userName })
+      .filter {
+        case (a, x) =>
+          ((a.mailAddress.toLowerCase === mailAddress.toLowerCase.bind) ||
+            (x.map { e =>
+                e.extraMailAddress.toLowerCase === mailAddress.toLowerCase.bind
+              }
+              .getOrElse(false.bind))) && (a.removed === false.bind, !includeRemoved)
+      }
+      .map { case (a, e) => a } firstOption
 
   def getAllUsers(includeRemoved: Boolean = true, includeGroups: Boolean = true)(implicit s: Session): List[Account] = {
     Accounts filter { t =>
@@ -199,6 +206,15 @@
   def updateAvatarImage(userName: String, image: Option[String])(implicit s: Session): Unit =
     Accounts.filter(_.userName === userName.bind).map(_.image.?).update(image)
 
+  def getAccountExtraMailAddresses(userName: String)(implicit s: Session): List[String] = {
+    AccountExtraMailAddresses.filter(_.userName === userName.bind).map(_.extraMailAddress) list
+  }
+
+  def updateAccountExtraMailAddresses(userName: String, mails: List[String])(implicit s: Session): Unit = {
+    AccountExtraMailAddresses.filter(_.userName === userName.bind).delete
+    mails.map(AccountExtraMailAddresses insert AccountExtraMailAddress(userName, _))
+  }
+
   def updateLastLoginDate(userName: String)(implicit s: Session): Unit =
     Accounts.filter(_.userName === userName.bind).map(_.lastLoginDate).update(currentDate)
 
diff --git a/src/main/twirl/gitbucket/core/account/edit.scala.html b/src/main/twirl/gitbucket/core/account/edit.scala.html
index 398c173..25c3dc0 100644
--- a/src/main/twirl/gitbucket/core/account/edit.scala.html
+++ b/src/main/twirl/gitbucket/core/account/edit.scala.html
@@ -1,4 +1,4 @@
-@(account: gitbucket.core.model.Account, info: Option[Any], error: Option[Any])(implicit context: gitbucket.core.controller.Context)
+@(account: gitbucket.core.model.Account, extraMailAddresses: List[String], info: Option[Any], error: Option[Any])(implicit context: gitbucket.core.controller.Context)
 @import gitbucket.core.util.LDAPUtil
 @import gitbucket.core.view.helpers
 @gitbucket.core.html.main("Edit your profile"){
@@ -31,6 +31,13 @@
                 <input type="text" name="mailAddress" id="mailAddress" class="form-control" value="@if(!LDAPUtil.isDummyMailAddress(account)){@account.mailAddress}"/>
                 <span id="error-mailAddress" class="error"></span>
               </fieldset>
+              <fieldset class="form-group" id="extraMailAddresses">
+                <span class="strong">Additional Mail Address:</span>
+                @extraMailAddresses.zipWithIndex.map { case (mail, idx) =>
+                  <input type="text" name="extraMailAddresses[@idx]" id="extraMailAddresses[@idx]" class="form-control extraMailAddress" value="@mail"/>
+                  <span id="error-extraMailAddresses_@idx" class="error"></span>
+                }
+              </fieldset>
               <fieldset class="form-group">
                 <label for="url" class="strong">URL (optional):</label>
                 <input type="text" name="url" id="url" class="form-control" value="@account.url"/>
@@ -62,6 +69,8 @@
 }
 <script>
 $(function(){
+  addExtraMailAddress();
+  $('#extraMailAddresses').on('change', '.extraMailAddress', checkExtraMailAddress);
   $('#save').click(function(){
     if($('#password').val() != ''){
       return confirm('Are you sure you want to change password?');
diff --git a/src/main/twirl/gitbucket/core/account/register.scala.html b/src/main/twirl/gitbucket/core/account/register.scala.html
index e1253aa..36db6e4 100644
--- a/src/main/twirl/gitbucket/core/account/register.scala.html
+++ b/src/main/twirl/gitbucket/core/account/register.scala.html
@@ -28,6 +28,9 @@
             <input type="text" name="mailAddress" id="mailAddress" class="form-control" value=""/>
             <span id="error-mailAddress" class="error"></span>
           </fieldset>
+          <div id="extraMailAddresses">
+            <span class="strong">Additional Mail Address:</span>
+          </div>
           <fieldset>
             <label for="url" class="strong">URL (optional):</label>
             <input type="text" name="url" id="url" class="form-control" value=""/>
@@ -52,4 +55,10 @@
     </form>
   </div>
 </div>
+<script>
+  $(function() {
+    addExtraMailAddress();
+    $('#extraMailAddresses').on('change', '.extraMailAddress', checkExtraMailAddress);
+  });
+</script>
 }
diff --git a/src/main/twirl/gitbucket/core/admin/user.scala.html b/src/main/twirl/gitbucket/core/admin/user.scala.html
index 7603415..ae791bb 100644
--- a/src/main/twirl/gitbucket/core/admin/user.scala.html
+++ b/src/main/twirl/gitbucket/core/admin/user.scala.html
@@ -1,4 +1,4 @@
-@(account: Option[gitbucket.core.model.Account], error: Option[Any] = None)(implicit context: gitbucket.core.controller.Context)
+@(account: Option[gitbucket.core.model.Account], extraMailAddresses: List[String], error: Option[Any] = None)(implicit context: gitbucket.core.controller.Context)
 @gitbucket.core.html.main(if(account.isEmpty) "New user" else "Update user"){
   @gitbucket.core.admin.html.menu("users"){
     @gitbucket.core.helper.html.error(error)
@@ -50,6 +50,13 @@
             </div>
             <input type="text" name="mailAddress" id="mailAddress" class="form-control" value="@account.map(_.mailAddress)"/>
           </fieldset>
+          <fieldset class="form-group" id="extraMailAddresses">
+            <span class="strong">Additional Mail Address:</span>
+            @extraMailAddresses.zipWithIndex.map { case (mail, idx) =>
+            <input type="text" name="extraMailAddresses[@idx]" id="extraMailAddresses[@idx]" class="form-control extraMailAddress" value="@mail"/>
+            <span id="error-extraMailAddresses_@idx" class="error"></span>
+            }
+          </fieldset>
           <fieldset class="form-group">
             <label class="strong">User Type:</label>
             <label class="radio" for="userType_Normal">
@@ -94,6 +101,8 @@
 }
 <script>
 $(function(){
+  addExtraMailAddress();
+  $('#extraMailAddresses').on('change', '.extraMailAddress', checkExtraMailAddress);
   $('#update').click(function(){
     if($('#password').val() != ''){
       return confirm('Are you sure you want to change password of this user?');
diff --git a/src/main/webapp/assets/common/js/gitbucket.js b/src/main/webapp/assets/common/js/gitbucket.js
index 3cbbcc4..a333d3c 100644
--- a/src/main/webapp/assets/common/js/gitbucket.js
+++ b/src/main/webapp/assets/common/js/gitbucket.js
@@ -694,3 +694,35 @@
   }
 };
 
+/**
+ * function for account extra mail address form control.
+ */
+function addExtraMailAddress() {
+  var fieldset = $('#extraMailAddresses');
+  var count = $('.extraMailAddress').length;
+  var html =   '<input type="text" name="extraMailAddresses[' + count + ']" id="extraMailAddresses[' + count + ']" class="form-control extraMailAddress"/>'
+  + '<span id="error-extraMailAddresses_' + count + '" class="error"></span>';
+  fieldset.append(html);
+}
+
+/**
+ * function for check account extra mail address form control.
+ */
+function checkExtraMailAddress(){
+  if ($(this).val() != ""){
+    var needAdd = true;
+    $('.extraMailAddress').each(function(){
+      if($(this).val() == ""){
+        needAdd = false;
+        return false;
+      }
+      return true;
+    });
+    if (needAdd){
+      addExtraMailAddress();
+    }
+  }
+  else {
+    $(this).remove();
+  }
+}