diff --git a/internal/translator/gemini/openai/responses/gemini_openai-responses_request.go b/internal/translator/gemini/openai/responses/gemini_openai-responses_request.go
index 463203a7..44b78346 100644
--- a/internal/translator/gemini/openai/responses/gemini_openai-responses_request.go
+++ b/internal/translator/gemini/openai/responses/gemini_openai-responses_request.go
@@ -1,6 +1,7 @@
 package responses
 
 import (
+	"encoding/json"
 	"strings"
 
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/translator/gemini/common"
@@ -340,7 +341,7 @@ func ConvertOpenAIResponsesRequestToGemini(modelName string, inputRawJSON []byte
 				// Set the raw JSON output directly (preserves string encoding)
 				if outputRaw != "" && outputRaw != "null" {
 					output := gjson.Parse(outputRaw)
-					if output.Type == gjson.JSON {
+					if output.Type == gjson.JSON && json.Valid([]byte(output.Raw)) {
 						functionResponse, _ = sjson.SetRaw(functionResponse, "functionResponse.response.result", output.Raw)
 					} else {
 						functionResponse, _ = sjson.Set(functionResponse, "functionResponse.response.result", outputRaw)