diff --git a/backend/app/services/doubao_service.py b/backend/app/services/doubao_service.py
index 7eece74..6384d1e 100644
--- a/backend/app/services/doubao_service.py
+++ b/backend/app/services/doubao_service.py
@@ -22,7 +22,7 @@ def synthesize_doubao(text, speed=1.0, pitch=0, volume=1.0, emotion='neutral'):
             'uid': 'military_tech_voice'
         },
         'audio': {
-            'voice_type': 'S_MK0j18H72',
+            'voice_type': 'S_LK0j18H72',
             'encoding': 'mp3',
             'speed_ratio': speed,
         },