diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5d5587d..c59e7c6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,7 +19,9 @@ jobs:
       - name: Set up .NET
         uses: actions/setup-dotnet@v6
         with:
-          dotnet-version: "8.0.x"
+          dotnet-version: |
+            8.0.x
+            10.0.x
 
       - name: Build
         run: dotnet build StreamFrame.slnx -c Release
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 866cf7e..4a7e28f 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -26,7 +26,9 @@ jobs:
       - name: Set up .NET
         uses: actions/setup-dotnet@v6
         with:
-          dotnet-version: "8.0.x"
+          dotnet-version: |
+            8.0.x
+            10.0.x
 
       - name: Verify tag matches csproj versions
         if: startsWith(github.ref, 'refs/tags/')
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b898ceb..7832eed 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 - CI Actions 升级到 Node 24 运行时：`actions/checkout@v7`、`actions/setup-dotnet@v6`、`softprops/action-gh-release@v3`（消除 Node 20 弃用告警）。
 
 ### 新增
+- 多目标框架（第一阶段）：`net8.0;net10.0`——net10 为当前 LTS（支持至 2028-11），CI 双框架全量测试；net9+ 目标采用 `System.Threading.Lock`。
 - 帧定界基准测试 `bench/StreamFrame.Benchmarks`（BenchmarkDotNet）：LengthPrefix/StxEtx 的流式 vs 纯函数编码对比与切帧吞吐，为"流式零拷贝"说法提供可复现数据。
 - 项目 LOGO（`docs/logo/`，SVG 母版 + PNG），README 双语版接入展示、两个 NuGet 包启用包图标（随下个版本发布生效）。
 - README 新增 CI 构建状态徽章；main 分支保护（必须走 PR 且 CI 通过、禁 force push/删除、强制线性历史）。
diff --git a/src/StreamFrame.Protocols.Xml/StreamFrame.Protocols.Xml.csproj b/src/StreamFrame.Protocols.Xml/StreamFrame.Protocols.Xml.csproj
index b10b3c2..71bff1b 100644
--- a/src/StreamFrame.Protocols.Xml/StreamFrame.Protocols.Xml.csproj
+++ b/src/StreamFrame.Protocols.Xml/StreamFrame.Protocols.Xml.csproj
@@ -17,7 +17,7 @@
   </ItemGroup>
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFrameworks>net8.0;net10.0</TargetFrameworks>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
diff --git a/src/StreamFrame/Connection/StreamConnection.cs b/src/StreamFrame/Connection/StreamConnection.cs
index 86e95dd..dd606ca 100644
--- a/src/StreamFrame/Connection/StreamConnection.cs
+++ b/src/StreamFrame/Connection/StreamConnection.cs
@@ -62,7 +62,11 @@ public string? RemoteIpAddress
     private readonly ICodec<TMessage> _codec;
     private readonly StreamConnectionOptions _options;
 
+#if NET9_0_OR_GREATER
+    private readonly Lock _sessionGate = new(); // System.Threading.Lock（net9+，比 monitor 锁更轻量）
+#else
     private readonly object _sessionGate = new();
+#endif
     private Pipe? _pipe;
     private CancellationTokenSource? _sessionCts;
     private Task? _receiveTask;
diff --git a/src/StreamFrame/StreamFrame.csproj b/src/StreamFrame/StreamFrame.csproj
index 6129063..8f68da2 100644
--- a/src/StreamFrame/StreamFrame.csproj
+++ b/src/StreamFrame/StreamFrame.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFrameworks>net8.0;net10.0</TargetFrameworks>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
@@ -31,7 +31,7 @@
     </PackageReference>
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="8.0.1" />
     <PackageReference Include="System.IO.Pipelines" Version="8.0.0" />
-    <PackageReference Include="System.Threading.Channels" Version="8.0.0" />
+    <!-- System.Threading.Channels 自 .NET Core 3.0 起内置共享框架，现代 .NET 无需引用；netstandard2.0 目标在兼容层另行引入 -->
   </ItemGroup>
 
   <ItemGroup>
diff --git a/test/StreamFrame.Tests/StreamFrame.Tests.csproj b/test/StreamFrame.Tests/StreamFrame.Tests.csproj
index d67f1b2..7e4b086 100644
--- a/test/StreamFrame.Tests/StreamFrame.Tests.csproj
+++ b/test/StreamFrame.Tests/StreamFrame.Tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFrameworks>net8.0;net10.0</TargetFrameworks>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>