diff --git a/ChangeLog.md b/ChangeLog.md
index 33fb425..f0aa8b8 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,8 @@
+## Release 1.2.1 - 2018/11/12
+
+* [fixed] Stop overwriting parameter type by `nil` [#278](https://github.com/fluent/fluentd-ui/pull/278) [#277](https://github.com/fluent/fluentd-ui/issues/277)
+* [maintenance] Update loofah to 2.2.3 [#279](https://github.com/fluent/fluentd-ui/pull/279)
+
 ## Release 1.2.0 - 2018/11/05
 
 * [maintenance] Add app/javascript/packs/components [#275](https://github.com/fluent/fluentd-ui/pull/275)
diff --git a/Gemfile.lock b/Gemfile.lock
index 6b2e906..93cd9c2 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    fluentd-ui (1.2.0)
+    fluentd-ui (1.2.1)
       addressable
       bootsnap (>= 1.1.0)
       bundler
diff --git a/lib/fluentd-ui/version.rb b/lib/fluentd-ui/version.rb
index 0c5aefa..4d4315a 100644
--- a/lib/fluentd-ui/version.rb
+++ b/lib/fluentd-ui/version.rb
@@ -1,3 +1,3 @@
 module FluentdUI
-  VERSION = "1.2.0"
+  VERSION = "1.2.1"
 end