diff --git a/pyproject.toml b/pyproject.toml
index 68b66670..e1aac71f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,6 +21,7 @@ requires = [
     "msgpack",
     "quart",
     "numba",
+    "opencv-python-headless<=4.11.0.86", # Required to avoid numpy version conflict with vllm
 ]
 build-backend = "setuptools.build_meta"
 
diff --git a/requirements.txt b/requirements.txt
index c133c628..0cb38311 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -15,6 +15,7 @@ torch>=2.7.1
 torchvision
 wheel
 pandas-stubs
+opencv-python-headless<=4.11.0.86 # Required to avoid numpy version conflict with vllm
 
 # requirements for disaggregated prefill
 msgpack