diff --git a/src/main/scala/gitbucket/core/util/StringUtil.scala b/src/main/scala/gitbucket/core/util/StringUtil.scala
index 5633598..d288d49 100644
--- a/src/main/scala/gitbucket/core/util/StringUtil.scala
+++ b/src/main/scala/gitbucket/core/util/StringUtil.scala
@@ -20,7 +20,7 @@
     md.digest.map(b => "%02x".format(b)).mkString
   }
 
-  def urlEncode(value: String): String = URLEncoder.encode(value, "UTF-8")
+  def urlEncode(value: String): String = URLEncoder.encode(value, "UTF-8").replace("+", "%20")
 
   def urlDecode(value: String): String = URLDecoder.decode(value, "UTF-8")
 
diff --git a/src/test/scala/gitbucket/core/util/StringUtilSpec.scala b/src/test/scala/gitbucket/core/util/StringUtilSpec.scala
index a0632eb..29fb0a7 100644
--- a/src/test/scala/gitbucket/core/util/StringUtilSpec.scala
+++ b/src/test/scala/gitbucket/core/util/StringUtilSpec.scala
@@ -4,11 +4,21 @@
 
 class StringUtilSpec extends Specification {
 
+  "urlEncode" should {
+    "encode whitespace to %20" in {
+      val encoded = StringUtil.urlEncode("aa bb")
+      encoded mustEqual "aa%20bb"
+    }
+  }
+
   "urlDecode" should {
     "decode encoded string to original string" in {
       val encoded = StringUtil.urlEncode("あいうえお")
       StringUtil.urlDecode(encoded) mustEqual "あいうえお"
     }
+    "decode en%20 to whitespace" in {
+      StringUtil.urlDecode("aa%20bb") mustEqual "aa bb"
+    }
   }
 
   "splitWords" should {