diff --git a/example/proxy/main.go b/example/proxy/main.go
index 6be328b0b07604e31049c9917729a8e46f1c6308..c5ede9c5f0eaa35dc604230cc6f260c21ad6d7bc 100644
--- a/example/proxy/main.go
+++ b/example/proxy/main.go
@@ -25,7 +25,7 @@ func main() {
 
 	r.HandleFunc("eth/*", func(w codec.ResponseWriter, r *codec.Request) {
 		var res json.RawMessage
-		err = c.Do(r.Context(), &res, r.Method, string(r.Params))
+		err = c.Do(r.Context(), &res, r.Method, json.RawMessage(r.Params))
 		w.Send(res, err)
 	})