--- a/python/mozbuild/mozbuild/virtualenv.py
+++ b/python/mozbuild/mozbuild/virtualenv.py
@@ -246,11 +246,12 @@
         if os.path.exists(self.virtualenv_root):
             shutil.rmtree(self.virtualenv_root)
 
         args = [
             python,
-            self.virtualenv_script_path,
+            "-m",
+            "virtualenv",
             # Without this, virtualenv.py may attempt to contact the outside
             # world and search for or download a newer version of pip,
             # setuptools, or wheel. This is bad for security, reproducibility,
             # and speed.
             "--no-download",