diff --git a/src/lm_polygraph/model_adapters/whitebox_model_vllm.py b/src/lm_polygraph/model_adapters/whitebox_model_vllm.py
index f95e7fc2..3135935b 100644
--- a/src/lm_polygraph/model_adapters/whitebox_model_vllm.py
+++ b/src/lm_polygraph/model_adapters/whitebox_model_vllm.py
@@ -68,7 +68,12 @@ def generate(self, *args, **kwargs):
                     },
                 ]
                 chats.append(chat)
-            output = self.model.chat(*args, chats, sampling_params)
+            output = self.model.chat(
+                *args,
+                chats,
+                sampling_params,
+                chat_template_kwargs={"enable_thinking": False},
+            )
         else:
             output = self.model.generate(*args, texts, sampling_params)
         return self.post_processing(output)