diff --git a/CHANGELOG.md b/CHANGELOG.md
index e309ff73..2a5726b6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,8 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 ## [Unreleased]
 
+## [2.66.6] - 2026-01-16
+
 - Update `prek@latest` to 0.2.29.
 
 - Update `zizmor@latest` to 1.21.0.
@@ -5365,7 +5367,8 @@ Note: This release is considered a breaking change because installing on version
 
 Initial release
 
-[Unreleased]: https://github.com/taiki-e/install-action/compare/v2.66.5...HEAD
+[Unreleased]: https://github.com/taiki-e/install-action/compare/v2.66.6...HEAD
+[2.66.6]: https://github.com/taiki-e/install-action/compare/v2.66.5...v2.66.6
 [2.66.5]: https://github.com/taiki-e/install-action/compare/v2.66.4...v2.66.5
 [2.66.4]: https://github.com/taiki-e/install-action/compare/v2.66.3...v2.66.4
 [2.66.3]: https://github.com/taiki-e/install-action/compare/v2.66.2...v2.66.3