diff --git a/examples/model_configs/vllm_model_config.yaml b/examples/model_configs/vllm_model_config.yaml
index be8941a66..5192cb558 100644
--- a/examples/model_configs/vllm_model_config.yaml
+++ b/examples/model_configs/vllm_model_config.yaml
@@ -10,5 +10,5 @@ model:
     top_k: -1
     min_p: 0.0
     top_p: 0.9
-    max_new_tokens: 100
+    max_new_tokens: 256
     stop_tokens: ["<EOS>", "<PAD>"]
diff --git a/src/lighteval/models/vllm/vllm_model.py b/src/lighteval/models/vllm/vllm_model.py
index 1742e6f30..105b3a22a 100644
--- a/src/lighteval/models/vllm/vllm_model.py
+++ b/src/lighteval/models/vllm/vllm_model.py
@@ -316,7 +316,9 @@ def _generate(
         sampling_params = self.sampling_params.clone() or SamplingParams()
         if generate:
             sampling_params.n = num_samples
-            sampling_params.max_tokens = max_new_tokens
+            sampling_params.max_tokens = (
+                max_new_tokens if sampling_params.max_tokens is None else sampling_params.max_tokens
+            )
             sampling_params.stop = stop_tokens
             sampling_params.logprobs = 1 if returns_logits else 0