diff --git a/product-source/hololake-platform/scripts/run-hololake-native-quality-gate.sh b/product-source/hololake-platform/scripts/run-hololake-native-quality-gate.sh
index aaa1495..6bc6a3e 100755
--- a/product-source/hololake-platform/scripts/run-hololake-native-quality-gate.sh
+++ b/product-source/hololake-platform/scripts/run-hololake-native-quality-gate.sh
@@ -4,6 +4,13 @@ set -Eeuo pipefail
 repository_root=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)
 receipt_path=${1:-}
 
+# Git exports repository-local environment variables while invoking hooks.
+# This repository's hook lives below the actual worktree root, so inherited
+# GIT_DIR/GIT_WORK_TREE values can make `git -C` inspect the wrong path and
+# falsely report a dirty source tree. Resolve the source root first, then make
+# every gate discover that worktree from its explicit `-C` argument.
+unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE GIT_PREFIX
+
 if [[ -z "${receipt_path}" ]]; then
   echo "usage: run-hololake-native-quality-gate.sh <receipt-output-outside-repository>" >&2
   exit 2