diff --git a/backend/src/lib/gemini.ts b/backend/src/lib/gemini.ts
index 66526849..e5ce3959 100644
--- a/backend/src/lib/gemini.ts
+++ b/backend/src/lib/gemini.ts
@@ -100,7 +100,7 @@ const generateTanka = async (originalText: string, image: File | null = null): P
     };
 
     const model = genAI.getGenerativeModel({
-      model: 'gemini-2.0-flash',
+      model: 'gemini-2.5-flash',
       systemInstruction: systemInstruction,
       generationConfig: {
         responseMimeType: 'application/json',