diff --git a/src/main/scala/app/SystemSettingsController.scala b/src/main/scala/app/SystemSettingsController.scala
index 076da08..42e52d7 100644
--- a/src/main/scala/app/SystemSettingsController.scala
+++ b/src/main/scala/app/SystemSettingsController.scala
@@ -99,6 +99,8 @@
   })
 
   get("/admin/plugins/available")(adminOnly {
+    // TODO Do periodical and asynchronous...?
+    PluginSystem.updateAllRepositories()
     admin.plugins.html.available(getAvailablePlugins())
   })
 
diff --git a/src/main/scala/plugin/PluginSystem.scala b/src/main/scala/plugin/PluginSystem.scala
index 539c992..df00943 100644
--- a/src/main/scala/plugin/PluginSystem.scala
+++ b/src/main/scala/plugin/PluginSystem.scala
@@ -7,6 +7,8 @@
 import util.Directory._
 import util.ControlUtil._
 import org.apache.commons.io.FileUtils
+import util.JGitUtil
+import org.eclipse.jgit.api.Git
 
 /**
  * Provides extension points to plug-ins.
@@ -48,6 +50,7 @@
     }
   }
 
+  // TODO Method name seems to not so good.
   def installPlugin(id: String): Unit = {
     val pluginDir = new java.io.File(PluginHome)
     val javaScriptFile = new java.io.File(pluginDir, id + "/plugin.js")
@@ -84,6 +87,25 @@
   case class RepositoryMenu(label: String, name: String, url: String, icon: String, condition: Context => Boolean)
   case class Action(path: String, function: (HttpServletRequest, HttpServletResponse) => Any)
 
+  /**
+   * Clone or pull all plugin repositories
+   *
+   * TODO Support plugin repository access through the proxy server
+   */
+  def updateAllRepositories(): Unit = {
+    repositories.foreach { repository =>
+      val dir = getPluginCacheDir()
+      val repo = new java.io.File(dir, repository.id)
+      if(repo.exists){
+        // pull if the repository is already cloned
+        Git.open(repo).pull().call()
+      } else {
+        // clone if the repository is not exist
+        Git.cloneRepository().setURI(repository.url).setDirectory(repo).call()
+      }
+    }
+  }
+
   // TODO This is a test
 //  addGlobalMenu("Google", "http://www.google.co.jp/", "data:image/png;base64,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")
 //    { context => context.loginAccount.isDefined }