diff --git a/relay/channel/gemini/relay-gemini.go b/relay/channel/gemini/relay-gemini.go
index e5eeca1c..18edfd04 100644
--- a/relay/channel/gemini/relay-gemini.go
+++ b/relay/channel/gemini/relay-gemini.go
@@ -133,12 +133,14 @@ func CovertGemini2OpenAI(textRequest dto.GeneralOpenAIRequest, info *relaycommon
 					IncludeThoughts: true,
 				}
 			} else {
-				budgetTokens := model_setting.GetGeminiSettings().ThinkingAdapterBudgetTokensPercentage * float64(geminiRequest.GenerationConfig.MaxOutputTokens)
-				clampedBudget := clampThinkingBudget(modelName, int(budgetTokens))
 				geminiRequest.GenerationConfig.ThinkingConfig = &GeminiThinkingConfig{
-					ThinkingBudget:  common.GetPointer(clampedBudget),
 					IncludeThoughts: true,
 				}
+				if geminiRequest.GenerationConfig.MaxOutputTokens > 0 {
+					budgetTokens := model_setting.GetGeminiSettings().ThinkingAdapterBudgetTokensPercentage * float64(geminiRequest.GenerationConfig.MaxOutputTokens)
+					clampedBudget := clampThinkingBudget(modelName, int(budgetTokens))
+					geminiRequest.GenerationConfig.ThinkingConfig.ThinkingBudget = common.GetPointer(clampedBudget)
+				}
 			}
 		} else if strings.HasSuffix(modelName, "-nothinking") {
 			if !isNew25Pro {