diff --git a/camel/model_backend.py b/camel/model_backend.py
index 18f3542e..d23330ef 100644
--- a/camel/model_backend.py
+++ b/camel/model_backend.py
@@ -69,7 +69,7 @@ class OpenAIModel(ModelBackend):
         num_max_completion_tokens = num_max_token - num_prompt_tokens
         self.model_config_dict['max_tokens'] = num_max_completion_tokens
         print("using model: {}".format(self.model_type.value))
-        response = openai.chat.completions.create(*args, **kwargs,
+        response = openai.ChatCompletion.create(*args, **kwargs,
                                                 model=self.model_type.value,
                                                 **self.model_config_dict)
         cost = prompt_cost(