diff --git a/examples/C#/C#checker/C#checker.csproj b/examples/C#/C#checker/C#checker.csproj
index 68bc2b5ad50cd37d0a11cc806a0d3742082c36a9..afeeaf3f01301210c0e945c8e02b40790ebec743 100644
--- a/examples/C#/C#checker/C#checker.csproj
+++ b/examples/C#/C#checker/C#checker.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
     <RootNamespace>C_checker</RootNamespace>
   </PropertyGroup>
 
diff --git a/examples/C#/TDengineTest/TDengineTest.csproj b/examples/C#/TDengineTest/TDengineTest.csproj
index af51b4eeecb33754e7005dd30c08cc56ee495fce..211c927d3d36df5941291319e3c85707610c6a8f 100644
--- a/examples/C#/TDengineTest/TDengineTest.csproj
+++ b/examples/C#/TDengineTest/TDengineTest.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/examples/C#/insertCn/insertCn.csproj b/examples/C#/insertCn/insertCn.csproj
index afd8df62e4f23807dcacaca52aaefc7cc0133a4a..69ddfdfbbff10fd9c26c92dcb8c8c2928b5c8511 100644
--- a/examples/C#/insertCn/insertCn.csproj
+++ b/examples/C#/insertCn/insertCn.csproj
@@ -6,7 +6,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
 </Project>
diff --git a/examples/C#/jsonTag/jsonTag.csproj b/examples/C#/jsonTag/jsonTag.csproj
index 2962d33a697e3b6fa6dd3f3390bfc8c2545ffaeb..eb33d899ac803baadbcfc4f1ee4a4888ed6434ab 100644
--- a/examples/C#/jsonTag/jsonTag.csproj
+++ b/examples/C#/jsonTag/jsonTag.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/examples/C#/schemaless/schemaless.csproj b/examples/C#/schemaless/schemaless.csproj
index 50e84ec1f91d6045c7fc6b967aa4c7b9bd27f6ad..c2369f3e8eaf82188f6c55b7bb6cf8564eb9017b 100644
--- a/examples/C#/schemaless/schemaless.csproj
+++ b/examples/C#/schemaless/schemaless.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/examples/C#/stmt/stmt.csproj b/examples/C#/stmt/stmt.csproj
index 629f476422fab58863bb57266054bf64ea772cd4..f0370cbf5684418edb026b56e306d7d7295a6638 100644
--- a/examples/C#/stmt/stmt.csproj
+++ b/examples/C#/stmt/stmt.csproj
@@ -6,7 +6,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
 </Project>
diff --git a/examples/C#/taosdemo/taosdemo.csproj b/examples/C#/taosdemo/taosdemo.csproj
index f6beeda56be3f8b09d108cc001729f8bf928b2a2..8d4b786ba3a99b600783a5b4ee55d99f03e47655 100644
--- a/examples/C#/taosdemo/taosdemo.csproj
+++ b/examples/C#/taosdemo/taosdemo.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
   </PropertyGroup>
 
diff --git a/tests/develop-test/3-connectors/c#/test.sh b/tests/develop-test/3-connectors/c#/test.sh
index 06d31887880feab20351995da0fc8f1342763e76..f77536c1fd8ba6595788fbcbcb5288bd72764e45 100755
--- a/tests/develop-test/3-connectors/c#/test.sh
+++ b/tests/develop-test/3-connectors/c#/test.sh
@@ -55,5 +55,5 @@ check $? insertCn.csproj
 cd ${WKC}/tests/examples/C#/taosdemo
 dotnet build -c Release
 tree | true
-./bin/Release/net6.0/taosdemo -c /etc/taos -y
+./bin/Release/net5.0/taosdemo -c /etc/taos -y
 check $? taosdemo