diff --git a/src/Assets/TestProjects/KitchenSink/TestApp/TestApp.csproj b/src/Assets/TestProjects/KitchenSink/TestApp/TestApp.csproj
index bb06727b9573..c66add5cd310 100644
--- a/src/Assets/TestProjects/KitchenSink/TestApp/TestApp.csproj
+++ b/src/Assets/TestProjects/KitchenSink/TestApp/TestApp.csproj
@@ -17,6 +17,7 @@
     <TieredCompilation>true</TieredCompilation>
     <TieredCompilationQuickJit>true</TieredCompilationQuickJit>
     <TieredCompilationQuickJitForLoops>true</TieredCompilationQuickJitForLoops>
+    <StartupHookSupport>false</StartupHookSupport>
     <EventSourceSupport>false</EventSourceSupport>
     <UseSystemResourceKeys>true</UseSystemResourceKeys>
     <EnableUnsafeUTF7Encoding>false</EnableUnsafeUTF7Encoding>
diff --git a/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.ILLink.targets b/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.ILLink.targets
index 7e97ab1accd2..37f5db7d436d 100644
--- a/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.ILLink.targets
+++ b/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.ILLink.targets
@@ -22,6 +22,16 @@ Copyright (c) .NET Foundation. All rights reserved.
     <_LinkSemaphore>$(IntermediateOutputPath)Link.semaphore</_LinkSemaphore>
   </PropertyGroup>
 
+  <!-- We disable startup hooks for trimmed apps here so that the feature
+       switch can flow to the runtimeconfig.json. Startup hooks are disabled
+       by default since they may require assemblies, types or members that
+       could be removed by the linker, causing a trimmed app to crash. -->
+  <PropertyGroup Condition="'$(StartupHookSupport)' == '' And
+                            '$(PublishTrimmed)' == 'true' And
+                            '$(_TargetFrameworkVersionWithoutV)' >= '6.0'">
+    <StartupHookSupport>false</StartupHookSupport>
+  </PropertyGroup>
+
   <!--
     ============================================================
                      ILLink
diff --git a/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Sdk.targets b/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Sdk.targets
index ac8adce6d755..2d8cb433c492 100644
--- a/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Sdk.targets
+++ b/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.Sdk.targets
@@ -400,6 +400,11 @@ Copyright (c) .NET Foundation. All rights reserved.
                                     Condition="'$(TieredCompilationQuickJitForLoops)' != ''"
                                     Value="$(TieredCompilationQuickJitForLoops)" />
 
+    <RuntimeHostConfigurationOption Include="System.StartupHookProvider.IsSupported"
+                                    Condition="'$(StartupHookSupport)' != ''"
+                                    Value="$(StartupHookSupport)"
+                                    Trim="true" />
+
     <RuntimeHostConfigurationOption Include="System.Text.Encoding.EnableUnsafeUTF7Encoding"
                                     Condition="'$(EnableUnsafeUTF7Encoding)' != ''"
                                     Value="$(EnableUnsafeUTF7Encoding)"
@@ -412,7 +417,6 @@ Copyright (c) .NET Foundation. All rights reserved.
     <RuntimeHostConfigurationOption Include="System.Threading.ThreadPool.MaxThreads"
                                     Condition="'$(ThreadPoolMaxThreads)' != ''"
                                     Value="$(ThreadPoolMaxThreads)" />
-
   </ItemGroup>
 
   <!--
diff --git a/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToPublishAProjectWithAllFeatures.cs b/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToPublishAProjectWithAllFeatures.cs
index b93ff93a4612..ce3b8cd90551 100644
--- a/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToPublishAProjectWithAllFeatures.cs
+++ b/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToPublishAProjectWithAllFeatures.cs
@@ -77,6 +77,7 @@ public void It_publishes_the_project_correctly(string targetFramework, string []
             ""System.Runtime.TieredCompilation"": true,
             ""System.Runtime.TieredCompilation.QuickJit"": true,
             ""System.Runtime.TieredCompilation.QuickJitForLoops"": true,
+            ""System.StartupHookProvider.IsSupported"": false,
             ""System.Text.Encoding.EnableUnsafeUTF7Encoding"": false,
             ""System.Threading.ThreadPool.MinThreads"": 2,
             ""System.Threading.ThreadPool.MaxThreads"": 9,
diff --git a/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToRunILLink.cs b/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToRunILLink.cs
index 08251a459901..d82fb5eabb5d 100644
--- a/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToRunILLink.cs
+++ b/src/Tests/Microsoft.NET.Publish.Tests/GivenThatWeWantToRunILLink.cs
@@ -18,6 +18,7 @@
 using Microsoft.NET.TestFramework.Assertions;
 using Microsoft.NET.TestFramework.Commands;
 using Microsoft.NET.TestFramework.ProjectConstruction;
+using Newtonsoft.Json.Linq;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -372,6 +373,40 @@ public void ILLink_verify_analysis_warnings_hello_world_app(string targetFramewo
             Assert.True(!missingWarnings.Any() && !extraWarnings.Any(), errorMessage);
         }
 
+        [Theory]
+        [InlineData("net5.0")]
+        [InlineData("net6.0")]
+        public void StartupHookSupport_is_false_by_default_on_trimmed_apps(string targetFramework)
+        {
+            var projectName = "HelloWorld";
+            var rid = EnvironmentInfo.GetCompatibleRid(targetFramework);
+
+            var testProject = CreateTestProjectForILLinkTesting(targetFramework, projectName);
+            var testAsset = _testAssetsManager.CreateTestProject(testProject, identifier: projectName);
+
+            var publishCommand = new PublishCommand(Log, Path.Combine(testAsset.TestRoot, testProject.Name));
+            publishCommand.Execute($"/p:RuntimeIdentifier={rid}", "/p:PublishTrimmed=true")
+                .Should().Pass();
+
+            string outputDirectory = publishCommand.GetOutputDirectory(targetFramework: targetFramework, runtimeIdentifier: rid).FullName;
+            string runtimeConfigFile = Path.Combine(outputDirectory, $"{projectName}.runtimeconfig.json");
+            string runtimeConfigContents = File.ReadAllText(runtimeConfigFile);
+
+
+            if (Version.TryParse(targetFramework.TrimStart("net".ToCharArray()), out Version parsedVersion) &&
+                parsedVersion.Major >= 6)
+            {
+                JObject runtimeConfig = JObject.Parse(runtimeConfigContents);
+                runtimeConfig["runtimeOptions"]["configProperties"]
+                    ["System.StartupHookProvider.IsSupported"].Value<bool>()
+                    .Should().Be(false);
+            }
+            else
+            {
+                runtimeConfigContents.Should().NotContain("System.StartupHookProvider.IsSupported");
+            }
+        }
+
         [Theory]
         [InlineData("netcoreapp3.0")]
         public void ILLink_accepts_root_descriptor(string targetFramework)