diff --git a/ChangeLog b/ChangeLog
index 8b5ec0f67b..e58c9df559 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Oct 27 16:33:47 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* tool/redmine-backporter.rb (rel): check the exception and show right
+	  message.
+
 Thu Oct 27 14:57:33 2016  Kazuki Yamaguchi  <k@rhe.jp>
 
 	* ext/socket/lib/socket.rb (UDPSocket#recvfrom_nonblock): [DOC] Remove
diff --git a/tool/redmine-backporter.rb b/tool/redmine-backporter.rb
index 1ac51b0dba..a9007e1a5e 100755
--- a/tool/redmine-backporter.rb
+++ b/tool/redmine-backporter.rb
@@ -419,7 +419,11 @@ eom
       begin
         res.value
       rescue
-        $stderr.puts "deployed redmine doesn't have https://github.com/ruby/bugs.ruby-lang.org/commit/01fbba60d68cb916ddbccc8a8710e68c5217171d\nask naruse or hsbt"
+        if $!.respond_to?(:response) && $!.response.is_a?(Net::HTTPConflict)
+          $stderr.puts "the revision has already related to the ticket"
+        else
+          $stderr.puts "deployed redmine doesn't have https://github.com/ruby/bugs.ruby-lang.org/commit/01fbba60d68cb916ddbccc8a8710e68c5217171d\nask naruse or hsbt"
+        end
         next
       end
       puts res.body