diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7e7ba0b..28ae75d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,16 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog],
 and this project adheres to [Semantic Versioning].
 
+## [0.5.1] - 2023-05-20
+
+### Added
+
+- `StampCreatedPayload`のテストを追加
+
+### Fixed
+
+- `time`featureで`StampCreatedPayload::event_time`がプライベートになる問題を修正
+
 ## [v0.5.0] - 2023-05-15
 
 ### Added
@@ -77,4 +87,4 @@ and this project adheres to [Semantic Versioning].
 [v0.3.1]: https://github.com/H1rono/traq-bot-http/rs/compare/v0.3.0..v0.3.1
 [v0.3.0]: https://github.com/H1rono/traq-bot-http/rs/compare/v0.2.0..v0.3.0
 [v0.2.0]: https://github.com/H1rono/traq-bot-http-rs/compare/v0.1.0..v0.2.0
-[v0.1.0]: https://github.com/H1rono/traq-bot-http-rs/releases/tag/v0.0.1
\ No newline at end of file
+[v0.1.0]: https://github.com/H1rono/traq-bot-http-rs/releases/tag/v0.0.1