diff --git a/tools/ci_build/build.py b/tools/ci_build/build.py
index 1bfb6bdc35..aa1845665a 100755
--- a/tools/ci_build/build.py
+++ b/tools/ci_build/build.py
@@ -18,7 +18,7 @@ from distutils.version import LooseVersion
 SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
 REPO_DIR = os.path.normpath(os.path.join(SCRIPT_DIR, "..", ".."))
 
-sys.path.append(os.path.join(REPO_DIR, "tools", "python"))
+sys.path.insert(0, os.path.join(REPO_DIR, "tools", "python"))
 
 
 from util import run  # noqa: E402