diff --git a/setup.py b/setup.py
index f9a5027e3..7f95bf093 100644
--- a/setup.py
+++ b/setup.py
@@ -525,6 +525,8 @@ def _env_enabled_any(names, default="1") -> bool:
             cutlass_root / "examples/common/include",
             cutlass_root / "tools/library/include",
         ]
+        if "GPTQMODEL_CUTLASS_DIR" not in os.environ:
+            os.environ["GPTQMODEL_CUTLASS_DIR"] = str(cutlass_root)
         cutlass_include_flags = [f"-I{path}" for path in cutlass_include_paths]
         extra_compile_args["cxx"] += cutlass_include_flags
         extra_compile_args["nvcc"] += cutlass_include_flags