diff --git a/plugin/thesaurus/chat.go b/plugin/thesaurus/chat.go
index 190eb013..5f011f9c 100644
--- a/plugin/thesaurus/chat.go
+++ b/plugin/thesaurus/chat.go
@@ -146,7 +146,7 @@ const (
 
 func match(l []string, seg *jieba.Segmenter) zero.Rule {
 	return func(ctx *zero.Ctx) bool {
-		return ctxext.JiebaSimilarity(0.8, seg, func(ctx *zero.Ctx) string {
+		return ctxext.JiebaSimilarity(0.66, seg, func(ctx *zero.Ctx) string {
 			return ctx.ExtractPlainText()
 		}, l...)(ctx)
 	}