diff --git a/ddl/ddl_api.go b/ddl/ddl_api.go
index 8ed18e44d3df5..d7648c1f63fde 100644
--- a/ddl/ddl_api.go
+++ b/ddl/ddl_api.go
@@ -1640,8 +1640,10 @@ func modifiableCharsetAndCollation(toCharset, toCollate, origCharset, origCollat
 	if !charset.ValidCharsetAndCollation(toCharset, toCollate) {
 		return ErrUnknownCharacterSet.GenWithStackByArgs(toCharset, toCollate)
 	}
-	if toCharset == charset.CharsetUTF8MB4 && origCharset == charset.CharsetUTF8 {
-		// TiDB only allow utf8 to be changed to utf8mb4.
+	if (origCharset == charset.CharsetUTF8 && toCharset == charset.CharsetUTF8MB4) ||
+		(origCharset == charset.CharsetUTF8 && toCharset == charset.CharsetUTF8) ||
+		(origCharset == charset.CharsetUTF8MB4 && toCharset == charset.CharsetUTF8MB4) {
+		// TiDB only allow utf8 to be changed to utf8mb4, or changing the collation when the charset is utf8/utf8mb4.
 		return nil
 	}