diff --git a/Directory.Packages.props b/Directory.Packages.props
index 59a5902..d27b894 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -30,6 +30,9 @@
     <PackageVersion Include="Npgsql" Version="10.0.3" />
     <PackageVersion Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="10.0.3" />
     <PackageVersion Include="Scalar.AspNetCore" Version="2.16.16" />
+    <PackageVersion Include="Senparc.Weixin" Version="6.25.0" />
+    <PackageVersion Include="Senparc.Weixin.MP" Version="16.25.1" />
+    <PackageVersion Include="Senparc.Weixin.WxOpen" Version="3.28.1" />
     <PackageVersion Include="Serilog.AspNetCore" Version="10.0.0" />
     <PackageVersion Include="Serilog.Enrichers.Environment" Version="3.0.1" />
     <PackageVersion Include="Serilog.Enrichers.Thread" Version="4.0.0" />
diff --git a/Tiku.Infrastructure/Auth/WechatOAuthClient.cs b/Tiku.Infrastructure/Auth/WechatOAuthClient.cs
index d2183f0..384c009 100644
--- a/Tiku.Infrastructure/Auth/WechatOAuthClient.cs
+++ b/Tiku.Infrastructure/Auth/WechatOAuthClient.cs
@@ -1,49 +1,65 @@
-using System.Net.Http.Json;
 using System.Text.Json;
+using Senparc.Weixin.MP.AdvancedAPIs;
+using Senparc.Weixin.WxOpen.AdvancedAPIs.Sns;
 using Tiku.Application.Auth;
 
 namespace Tiku.Infrastructure.Auth;
 
-public sealed class WechatOAuthClient(HttpClient httpClient) : IWechatOAuthClient
+public sealed class WechatOAuthClient : IWechatOAuthClient
 {
-    private static readonly Uri WebAccessTokenEndpoint = new("https://api.weixin.qq.com/sns/oauth2/access_token");
-    private static readonly Uri WebUserInfoEndpoint = new("https://api.weixin.qq.com/sns/userinfo");
-    private static readonly Uri MiniAppCode2SessionEndpoint = new("https://api.weixin.qq.com/sns/jscode2session");
-
     public async Task<WechatIdentity> ExchangeWebCodeAsync(
         WechatProviderOptions options,
         string code,
         CancellationToken cancellationToken = default)
     {
-        var tokenUri = BuildUri(WebAccessTokenEndpoint, new Dictionary<string, string>
-        {
-            ["appid"] = options.AppId,
-            ["secret"] = options.AppSecret,
-            ["code"] = code,
-            ["grant_type"] = "authorization_code"
-        });
-        using var tokenDocument = await GetWechatJsonAsync(tokenUri, cancellationToken);
-        var token = tokenDocument.RootElement;
-        var accessToken = RequiredString(token, "access_token", "wechat_access_token_missing");
-        var openId = RequiredString(token, "openid", "wechat_openid_missing");
-        var unionId = OptionalString(token, "unionid");
+        cancellationToken.ThrowIfCancellationRequested();
 
-        var userInfoUri = BuildUri(WebUserInfoEndpoint, new Dictionary<string, string>
+        try
         {
-            ["access_token"] = accessToken,
-            ["openid"] = openId,
-            ["lang"] = "zh_CN"
-        });
-        using var userDocument = await GetWechatJsonAsync(userInfoUri, cancellationToken);
-        var user = userDocument.RootElement;
+            var token = await OAuthApi.GetAccessTokenAsync(
+                options.AppId,
+                options.AppSecret,
+                code,
+                "authorization_code");
+            cancellationToken.ThrowIfCancellationRequested();
+            EnsureSuccess(token.ErrorCodeValue, token.errmsg);
 
-        return new WechatIdentity(
-            openId,
-            OptionalString(user, "unionid") ?? unionId,
-            OptionalString(user, "nickname"),
-            OptionalString(user, "headimgurl"),
-            null,
-            user.GetRawText());
+            if (string.IsNullOrWhiteSpace(token.access_token))
+            {
+                throw new InvalidCredentialsException("wechat_access_token_missing");
+            }
+
+            if (string.IsNullOrWhiteSpace(token.openid))
+            {
+                throw new InvalidCredentialsException("wechat_openid_missing");
+            }
+
+            var user = await OAuthApi.GetUserInfoAsync(
+                token.access_token,
+                token.openid,
+                Senparc.Weixin.Language.zh_CN);
+            cancellationToken.ThrowIfCancellationRequested();
+
+            return new WechatIdentity(
+                token.openid.Trim(),
+                FirstNonBlank(user.unionid, token.unionid),
+                NullIfBlank(user.nickname),
+                NullIfBlank(user.headimgurl),
+                null,
+                SerializeRaw(new
+                {
+                    accessToken = token,
+                    user
+                }));
+        }
+        catch (InvalidCredentialsException)
+        {
+            throw;
+        }
+        catch (Exception exception)
+        {
+            throw new InvalidCredentialsException(MapWechatException(exception));
+        }
     }
 
     public async Task<WechatIdentity> ExchangeMiniAppCodeAsync(
@@ -51,65 +67,78 @@ public sealed class WechatOAuthClient(HttpClient httpClient) : IWechatOAuthClien
         string code,
         CancellationToken cancellationToken = default)
     {
-        var uri = BuildUri(MiniAppCode2SessionEndpoint, new Dictionary<string, string>
-        {
-            ["appid"] = options.AppId,
-            ["secret"] = options.AppSecret,
-            ["js_code"] = code,
-            ["grant_type"] = "authorization_code"
-        });
-        using var document = await GetWechatJsonAsync(uri, cancellationToken);
-        var root = document.RootElement;
+        cancellationToken.ThrowIfCancellationRequested();
 
-        return new WechatIdentity(
-            RequiredString(root, "openid", "wechat_openid_missing"),
-            OptionalString(root, "unionid"),
-            null,
-            null,
-            RequiredString(root, "session_key", "wechat_session_key_missing"),
-            root.GetRawText());
+        try
+        {
+            var result = await SnsApi.JsCode2JsonAsync(
+                options.AppId,
+                options.AppSecret,
+                code,
+                "authorization_code");
+            cancellationToken.ThrowIfCancellationRequested();
+            EnsureSuccess(result.ErrorCodeValue, result.errmsg);
+
+            if (string.IsNullOrWhiteSpace(result.openid))
+            {
+                throw new InvalidCredentialsException("wechat_openid_missing");
+            }
+
+            if (string.IsNullOrWhiteSpace(result.session_key))
+            {
+                throw new InvalidCredentialsException("wechat_session_key_missing");
+            }
+
+            return new WechatIdentity(
+                result.openid.Trim(),
+                NullIfBlank(result.unionid),
+                null,
+                null,
+                result.session_key.Trim(),
+                SerializeRaw(result));
+        }
+        catch (InvalidCredentialsException)
+        {
+            throw;
+        }
+        catch (Exception exception)
+        {
+            throw new InvalidCredentialsException(MapWechatException(exception));
+        }
     }
 
-    private async Task<JsonDocument> GetWechatJsonAsync(
-        Uri uri,
-        CancellationToken cancellationToken)
+    private static void EnsureSuccess(int errorCode, string? errorMessage)
     {
-        using var response = await httpClient.GetAsync(uri, cancellationToken);
-        response.EnsureSuccessStatusCode();
-        var document = await response.Content.ReadFromJsonAsync<JsonDocument>(cancellationToken)
-            ?? throw new InvalidCredentialsException("wechat_empty_response");
-
-        if (document.RootElement.TryGetProperty("errcode", out var errcode) &&
-            errcode.ValueKind == JsonValueKind.Number &&
-            errcode.GetInt32() != 0)
+        if (errorCode == 0)
         {
-            throw new InvalidCredentialsException("wechat_code_exchange_failed");
+            return;
         }
 
-        return document;
+        throw new InvalidCredentialsException(
+            string.IsNullOrWhiteSpace(errorMessage)
+                ? "wechat_code_exchange_failed"
+                : $"wechat_code_exchange_failed:{errorCode}");
     }
 
-    private static Uri BuildUri(Uri endpoint, IReadOnlyDictionary<string, string> query)
+    private static string SerializeRaw<T>(T value)
     {
-        var builder = new UriBuilder(endpoint);
-        builder.Query = string.Join(
-            '&',
-            query.Select(pair =>
-                $"{Uri.EscapeDataString(pair.Key)}={Uri.EscapeDataString(pair.Value)}"));
-        return builder.Uri;
+        return JsonSerializer.Serialize(value);
     }
 
-    private static string RequiredString(JsonElement element, string property, string errorCode)
+    private static string? FirstNonBlank(params string?[] values)
     {
-        return OptionalString(element, property) ?? throw new InvalidCredentialsException(errorCode);
+        return values.Select(NullIfBlank).FirstOrDefault(value => value is not null);
     }
 
-    private static string? OptionalString(JsonElement element, string property)
+    private static string? NullIfBlank(string? value)
     {
-        return element.TryGetProperty(property, out var value) &&
-               value.ValueKind == JsonValueKind.String &&
-               !string.IsNullOrWhiteSpace(value.GetString())
-            ? value.GetString()!.Trim()
-            : null;
+        return string.IsNullOrWhiteSpace(value) ? null : value.Trim();
+    }
+
+    private static string MapWechatException(Exception exception)
+    {
+        return exception is HttpRequestException
+            ? "wechat_http_error"
+            : "wechat_code_exchange_failed";
     }
 }
diff --git a/Tiku.Infrastructure/DependencyInjection.cs b/Tiku.Infrastructure/DependencyInjection.cs
index 5f11a11..55e5971 100644
--- a/Tiku.Infrastructure/DependencyInjection.cs
+++ b/Tiku.Infrastructure/DependencyInjection.cs
@@ -40,7 +40,7 @@ public static class DependencyInjection
         services.AddScoped<ITokenService, TokenService>();
         services.AddScoped<ISessionService, SessionService>();
         services.AddScoped<ISmsVerificationService, SmsVerificationService>();
-        services.AddHttpClient<IWechatOAuthClient, WechatOAuthClient>();
+        services.AddScoped<IWechatOAuthClient, WechatOAuthClient>();
         services.AddScoped<IAuthService, AuthService>();
         services.AddScoped<ICatalogQueryService, CatalogQueryService>();
         services.AddScoped<IContentNavigationQueryService, ContentNavigationQueryService>();
diff --git a/Tiku.Infrastructure/Tiku.Infrastructure.csproj b/Tiku.Infrastructure/Tiku.Infrastructure.csproj
index 800c076..9092d95 100644
--- a/Tiku.Infrastructure/Tiku.Infrastructure.csproj
+++ b/Tiku.Infrastructure/Tiku.Infrastructure.csproj
@@ -14,6 +14,9 @@
     <PackageReference Include="Microsoft.Extensions.Options" />
     <PackageReference Include="Npgsql" />
     <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <PackageReference Include="Senparc.Weixin" />
+    <PackageReference Include="Senparc.Weixin.MP" />
+    <PackageReference Include="Senparc.Weixin.WxOpen" />
     <PackageReference Include="System.IdentityModel.Tokens.Jwt" />
   </ItemGroup>