diff --git a/src/TelegramPanel.Web/Components/Pages/Settings.razor b/src/TelegramPanel.Web/Components/Pages/Settings.razor
index b1472f6..5719bf7 100644
--- a/src/TelegramPanel.Web/Components/Pages/Settings.razor
+++ b/src/TelegramPanel.Web/Components/Pages/Settings.razor
@@ -10,6 +10,7 @@
 @inject ISnackbar Snackbar
 @inject IDialogService DialogService
 @inject IWebHostEnvironment Environment
+@using TelegramPanel.Web.Services
 
 <PageTitle>系统设置 - Telegram Panel</PageTitle>
 
@@ -150,7 +151,7 @@
     private int logRetentionDays = 30;
     private bool syncing = false;
 
-    private string LocalConfigPath => System.IO.Path.Combine(Environment.ContentRootPath, "appsettings.local.json");
+    private string LocalConfigPath => LocalConfigFile.ResolvePath(Configuration, Environment);
     private bool LocalConfigExists => System.IO.File.Exists(LocalConfigPath);
 
     protected override void OnInitialized()
@@ -188,8 +189,18 @@
             // 配置变更后清理客户端缓存，确保后续操作使用新 ApiId/ApiHash
             await TelegramClientPool.RemoveAllClientsAsync();
 
-            var fileInfo = new System.IO.FileInfo(localConfigPath);
-            Snackbar.Add($"API 配置已保存：{localConfigPath}（{fileInfo.Length} bytes）。已清理 Telegram 客户端缓存，后续操作将使用新配置。", Severity.Success);
+            string sizeHint;
+            try
+            {
+                var fileInfo = new System.IO.FileInfo(localConfigPath);
+                sizeHint = $"（{fileInfo.Length} bytes）";
+            }
+            catch
+            {
+                sizeHint = "";
+            }
+
+            Snackbar.Add($"API 配置已保存：{localConfigPath}{sizeHint}。已清理 Telegram 客户端缓存，后续操作将使用新配置。", Severity.Success);
             StateHasChanged();
         }
         catch (Exception ex)
@@ -240,11 +251,9 @@
     private async Task SaveLocalConfigAsync(System.Text.Json.Nodes.JsonObject root)
     {
         var json = root.ToJsonString(new System.Text.Json.JsonSerializerOptions { WriteIndented = true });
-        await System.IO.File.WriteAllTextAsync(
-            LocalConfigPath,
-            json,
-            new System.Text.UTF8Encoding(encoderShouldEmitUTF8Identifier: false)
-        );
+        var path = LocalConfigPath;
+        await LocalConfigFile.EnsureExistsAsync(path);
+        await LocalConfigFile.WriteJsonAtomicallyAsync(path, json);
     }
 
     private static System.Text.Json.Nodes.JsonObject EnsureObject(System.Text.Json.Nodes.JsonObject root, string key)
diff --git a/src/TelegramPanel.Web/Program.cs b/src/TelegramPanel.Web/Program.cs
index a904e8a..affa17f 100644
--- a/src/TelegramPanel.Web/Program.cs
+++ b/src/TelegramPanel.Web/Program.cs
@@ -18,7 +18,7 @@ var builder = WebApplication.CreateBuilder(args);
 // 直接加载会抛 FileNotFoundException 导致容器不断重启，因此这里先确保文件存在一个空 JSON。
 try
 {
-    var localOverridePath = Path.Combine(builder.Environment.ContentRootPath, "appsettings.local.json");
+    var localOverridePath = LocalConfigFile.ResolvePath(builder.Configuration, builder.Environment);
     if (!File.Exists(localOverridePath))
         File.WriteAllText(localOverridePath, "{}", new System.Text.UTF8Encoding(encoderShouldEmitUTF8Identifier: false));
 }
@@ -31,7 +31,8 @@ try
 {
     // 注意：如果该路径是“悬空符号链接”，配置系统可能会认为文件存在并尝试打开，从而抛 FileNotFoundException。
     // 本地覆盖配置不应该阻塞启动，因此这里兜底吞掉 FileNotFoundException。
-    builder.Configuration.AddJsonFile("appsettings.local.json", optional: true, reloadOnChange: true);
+    var localOverridePath = LocalConfigFile.ResolvePath(builder.Configuration, builder.Environment);
+    builder.Configuration.AddJsonFile(localOverridePath, optional: true, reloadOnChange: true);
 }
 catch (FileNotFoundException ex)
 {
diff --git a/src/TelegramPanel.Web/Services/LocalConfigFile.cs b/src/TelegramPanel.Web/Services/LocalConfigFile.cs
new file mode 100644
index 0000000..412f153
--- /dev/null
+++ b/src/TelegramPanel.Web/Services/LocalConfigFile.cs
@@ -0,0 +1,46 @@
+using System.Text;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.Extensions.Configuration;
+
+namespace TelegramPanel.Web.Services;
+
+public static class LocalConfigFile
+{
+    public static string ResolvePath(IConfiguration configuration, IWebHostEnvironment environment)
+    {
+        var configured = (configuration["LocalConfig:Path"] ?? "").Trim();
+        if (!string.IsNullOrWhiteSpace(configured))
+            return configured;
+
+        // Docker 部署默认持久化目录为 /data（docker-compose 挂载 ./docker-data:/data）
+        // 即便没有显式配置，也优先写到 /data，避免写入镜像层 /app 导致丢失或权限问题。
+        if (Directory.Exists("/data"))
+            return "/data/appsettings.local.json";
+
+        return Path.Combine(environment.ContentRootPath, "appsettings.local.json");
+    }
+
+    public static async Task EnsureExistsAsync(string path, CancellationToken cancellationToken = default)
+    {
+        var dir = Path.GetDirectoryName(path);
+        if (!string.IsNullOrWhiteSpace(dir))
+            Directory.CreateDirectory(dir);
+
+        if (File.Exists(path))
+            return;
+
+        await File.WriteAllTextAsync(path, "{}", new UTF8Encoding(encoderShouldEmitUTF8Identifier: false), cancellationToken);
+    }
+
+    public static async Task WriteJsonAtomicallyAsync(string path, string json, CancellationToken cancellationToken = default)
+    {
+        var dir = Path.GetDirectoryName(path);
+        if (!string.IsNullOrWhiteSpace(dir))
+            Directory.CreateDirectory(dir);
+
+        var tmp = $"{path}.tmp";
+        await File.WriteAllTextAsync(tmp, json, new UTF8Encoding(encoderShouldEmitUTF8Identifier: false), cancellationToken);
+        File.Move(tmp, path, overwrite: true);
+    }
+}
+