diff --git a/bin/update_port.sh b/bin/update_port.sh
index 27dfe3e..dd3f554 100644
--- a/bin/update_port.sh
+++ b/bin/update_port.sh
@@ -1,5 +1,49 @@
 #!/bin/bash
 
+# 查找空闲端口
+find_free_port() {
+  local start="${1:-10001}"
+  local max="${2:-65535}"
+
+  # 收集当前监听端口（TCP + UDP）
+  local used_ports raw
+  if command -v ss >/dev/null 2>&1; then
+    raw=$(ss -lntu 2>/dev/null || true)
+    used_ports=$(printf "%s\n" "$raw" | awk '{print $5}' | sed -n '2,$p' | sed -E 's/.*[:]//g' | sed '/^$/d')
+  elif command -v netstat >/dev/null 2>&1; then
+    raw=$(netstat -lntu 2>/dev/null || true)
+    used_ports=$(printf "%s\n" "$raw" | awk '{print $4}' | sed -n '2,$p' | sed -E 's/.*[:]//g' | sed '/^$/d')
+  elif command -v lsof >/dev/null 2>&1; then
+    raw=$(lsof -i -P -n 2>/dev/null || true)
+    used_ports=$(printf "%s\n" "$raw" | awk '/LISTEN/ {print $9}' | sed -E 's/.*[:]//g' | sed '/^$/d')
+  else
+    echo "Error: neither ss, netstat nor lsof is available to check listening ports." >&2
+    return 2
+  fi
+
+  # 用关联数组记录已占用端口（需要 bash 4+）
+  declare -A used_map
+  local p
+  for p in $used_ports; do
+    # 过滤掉非数字
+    if [[ $p =~ ^[0-9]+$ ]]; then
+      used_map["$p"]=1
+    fi
+  done
+
+  # 从 start 到 max 逐个检查
+  for ((port = start; port <= max; port++)); do
+    if [[ -z "${used_map[$port]}" ]]; then
+      echo "$port"
+      return 0
+    fi
+  done
+
+  # 没找到可用端口
+  echo "Error: No available port found in range $start-$max" >&2
+  return 1
+}
+
 # 修改端口的函数
 change_port() {
     local script_dir=$(cd "$(dirname "$0")"; pwd)
@@ -9,6 +53,16 @@ change_port() {
     local old_port=$(jq -r '.listen' "$config_dir/config.json" | awk -F : '{print $2}')
     local port
     read -p "请输入新的端口[当前端口: $old_port]: " port
+
+    # 如果输入端口为空, 查找空闲端口
+    if [[ -z "$port" ]]; then
+        port=$(find_free_port)
+        if [[ -z "$port" ]]; then
+            echo "未能找到可用端口！" >&2
+            return 1
+        fi
+        echo "未输入端口，自动分配可用端口: $port"
+    fi
     
     modify_json_file "$config_dir/config.json" ".listen" ":$port"