diff --git a/CHANGELOG.md b/CHANGELOG.md
index af3ae69e55b..10b9d81a5af 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,7 @@ Compatibility:
 * Set `RbConfig::CONFIG['archincludedir']` (#3396, @andrykonchin).
 * Support the index/length arguments for the string argument to `String#bytesplice` added in 3.3 (#3656, @rwstauner).
 * Implement `rb_str_strlen()` (#3697, @Th3-M4jor).
+* Implement `rb_enc_interned_str()` (#3706, @Th3-M4jor).
 
 Performance: