diff --git a/start.sh b/start.sh
index 9fa8ed2c..d9a775f8 100644
--- a/start.sh
+++ b/start.sh
@@ -7,12 +7,14 @@ export VERSION=$(cat /app/version)
 
 ENV_FILE="/app/.env"
 
-# 读取 .env 文件并导出环境变量，跳过已存在的环境变量
-grep -v -e '^#' -e '^$' "$ENV_FILE" | while read -r line; do
-    key=$(echo "$line" | cut -d '=' -f 1)
-    if [ -z "${!key+x}" ]; then
-        # 导出整个键值对
-        export "$line"
+grep -v -e '^#' -e '^$' "$ENV_FILE" | while IFS='=' read -r key value; do
+    if [ -z "$key" ] || [ -z "$value" ]; then
+        continue
+    fi
+
+    if ! declare -p "$key" &>/dev/null; then
+        echo "Setting $key=$value"
+        export "$key=$value"
     fi
 done