diff --git a/eng/codeOptimization.targets b/eng/codeOptimization.targets
index 24e9c761407cfb..cbd2474984592a 100644
--- a/eng/codeOptimization.targets
+++ b/eng/codeOptimization.targets
@@ -9,7 +9,7 @@
            IBCMerge optimizations on Mac for now to unblock the offical build.
            See issue https://github.com/dotnet/runtime/issues/33303
       -->
-      <IsEligibleForNgenOptimization Condition="'$(TargetOS)' == 'OSX' or '$(TargetOS)' == 'iOS'">false</IsEligibleForNgenOptimization>
+      <IsEligibleForNgenOptimization Condition="'$(TargetOS)' == 'OSX'">false</IsEligibleForNgenOptimization>
   </PropertyGroup>
 
   <Target Name="SetApplyNgenOptimization"
diff --git a/eng/install-native-dependencies.sh b/eng/install-native-dependencies.sh
index e837b017c7cba1..a73d4918c521bb 100644
--- a/eng/install-native-dependencies.sh
+++ b/eng/install-native-dependencies.sh
@@ -23,18 +23,8 @@ elif [ "$1" = "OSX" ]; then
     if [ "$?" != "0" ]; then
         exit 1;
     fi
-elif [ "$1" = "iOS" ]; then
-    brew update
-    brew upgrade
-    if [ "$?" != "0" ]; then
-        exit 1;
-    fi
-    brew install openssl autoconf automake libtool pkg-config python3
-    if [ "$?" != "0" ]; then
-        exit 1;
-    fi
 else
-    echo "Must pass \"Linux\", \"iOS\" or \"OSX\" as first argument."
+    echo "Must pass \"Linux\" or \"OSX\" as first argument."
     exit 1
 fi
 
diff --git a/eng/pipelines/common/platform-matrix.yml b/eng/pipelines/common/platform-matrix.yml
index f67710276d1f25..4858cc154478c6 100644
--- a/eng/pipelines/common/platform-matrix.yml
+++ b/eng/pipelines/common/platform-matrix.yml
@@ -198,66 +198,6 @@ jobs:
 #         asArray: []
 #       ${{ insert }}: ${{ parameters.jobParameters }}
 
-# iOS x64
-
-- ${{ if or(containsValue(parameters.platforms, 'iOS_x64'), eq(parameters.platformGroup, 'all')) }}:
-  - template: xplat-setup.yml
-    parameters:
-      jobTemplate: ${{ parameters.jobTemplate }}
-      helixQueuesTemplate: ${{ parameters.helixQueuesTemplate }}
-      osGroup: iOS
-      archType: x64
-      platform: iOS_x64
-      jobParameters:
-        runtimeFlavor: mono
-        stagedBuild: ${{ parameters.stagedBuild }}
-        buildConfig: ${{ parameters.buildConfig }}
-        ${{ if eq(parameters.passPlatforms, true) }}:
-          platforms: ${{ parameters.platforms }}
-        helixQueueGroup: ${{ parameters.helixQueueGroup }}
-        managedTestBuildOsGroup: OSX
-        ${{ insert }}: ${{ parameters.jobParameters }}
-
-# iOS arm
-
-- ${{ if or(containsValue(parameters.platforms, 'iOS_arm'), eq(parameters.platformGroup, 'all')) }}:
-  - template: xplat-setup.yml
-    parameters:
-      jobTemplate: ${{ parameters.jobTemplate }}
-      helixQueuesTemplate: ${{ parameters.helixQueuesTemplate }}
-      osGroup: iOS
-      archType: arm
-      platform: iOS_x64
-      jobParameters:
-        runtimeFlavor: mono
-        stagedBuild: ${{ parameters.stagedBuild }}
-        buildConfig: ${{ parameters.buildConfig }}
-        ${{ if eq(parameters.passPlatforms, true) }}:
-          platforms: ${{ parameters.platforms }}
-        helixQueueGroup: ${{ parameters.helixQueueGroup }}
-        managedTestBuildOsGroup: OSX
-        ${{ insert }}: ${{ parameters.jobParameters }}
-
-# iOS arm64
-
-- ${{ if or(containsValue(parameters.platforms, 'iOS_arm64'), eq(parameters.platformGroup, 'all')) }}:
-  - template: xplat-setup.yml
-    parameters:
-      jobTemplate: ${{ parameters.jobTemplate }}
-      helixQueuesTemplate: ${{ parameters.helixQueuesTemplate }}
-      osGroup: iOS
-      archType: arm64
-      platform: iOS_x64
-      jobParameters:
-        runtimeFlavor: mono
-        stagedBuild: ${{ parameters.stagedBuild }}
-        buildConfig: ${{ parameters.buildConfig }}
-        ${{ if eq(parameters.passPlatforms, true) }}:
-          platforms: ${{ parameters.platforms }}
-        helixQueueGroup: ${{ parameters.helixQueueGroup }}
-        managedTestBuildOsGroup: OSX
-        ${{ insert }}: ${{ parameters.jobParameters }}
-
 # macOS x64
 
 - ${{ if or(containsValue(parameters.platforms, 'OSX_x64'), eq(parameters.platformGroup, 'all')) }}:
diff --git a/eng/pipelines/common/xplat-setup.yml b/eng/pipelines/common/xplat-setup.yml
index d644907ae3d63d..817443e041e4cf 100644
--- a/eng/pipelines/common/xplat-setup.yml
+++ b/eng/pipelines/common/xplat-setup.yml
@@ -87,10 +87,6 @@ jobs:
         ${{ if eq(parameters.osGroup, 'OSX') }}:
           vmImage: 'macOS-10.14'
 
-        # Public OSX Build Pool
-        ${{ if eq(parameters.osGroup, 'iOS') }}:
-          vmImage: 'macOS-10.14'
-
         # Official Build Windows Pool
         ${{ if and(eq(parameters.osGroup, 'Windows_NT'), ne(variables['System.TeamProject'], 'public')) }}:
           name: NetCoreInternal-Pool
diff --git a/eng/pipelines/libraries/base-job.yml b/eng/pipelines/libraries/base-job.yml
index e24d0d3328bbc4..85ea99f75c30f5 100644
--- a/eng/pipelines/libraries/base-job.yml
+++ b/eng/pipelines/libraries/base-job.yml
@@ -40,8 +40,7 @@ jobs:
         - _BuildConfig: ${{ parameters.buildConfig }}
 
         - _msbuildCommonParameters: ''
-        # rename this variable, due to collision with build-native.proj
-        - _stripSymbolsArgYaml: ''
+        - _stripSymbolsArg: ''
         - _runtimeOSArg: ''
         - _finalFrameworkArg: ''
         - _buildScript: $(_buildScriptFileName)$(scriptExt)
@@ -71,10 +70,6 @@ jobs:
         - ${{ if eq(parameters.osGroup, 'WebAssembly') }}:
           - _runtimeOSArg: -os ${{ parameters.osGroup }}
 
-        # force a value for OS when cross-building iOS on OSX
-        - ${{ if eq(parameters.osGroup, 'iOS') }}:
-          - _runtimeOSArg: -os ${{ parameters.osGroup }}
-
         - ${{ if ne(parameters.framework, '') }}:
           - _finalFrameworkArg: -framework ${{ parameters.framework }}
           - _extraHelixArguments: /p:BuildTargetFramework=${{ parameters.framework }}
@@ -112,9 +107,9 @@ jobs:
         - ${{ if ne(parameters.osGroup, 'Windows_NT') }}:
           - _buildScript: ./$(_buildScriptFileName)$(scriptExt)
           - ${{ if eq(parameters.isOfficialBuild, 'true') }}:
-            - _stripSymbolsArgYaml: -stripSymbols
+            - _stripSymbolsArg: -stripSymbols
 
-        - _buildArguments: -configuration ${{ parameters.buildConfig }} -ci -arch ${{ parameters.archType }} $(_finalFrameworkArg) $(_stripSymbolsArgYaml) $(_testScopeArg) $(_warnAsErrorArg) $(_runtimeOSArg) $(_msbuildCommonParameters) $(_runtimeArtifactsPathArg) $(_crossBuildPropertyArg)
+        - _buildArguments: -configuration ${{ parameters.buildConfig }} -ci -arch ${{ parameters.archType }} $(_finalFrameworkArg) $(_stripSymbolsArg) $(_testScopeArg) $(_warnAsErrorArg) $(_runtimeOSArg) $(_msbuildCommonParameters) $(_runtimeArtifactsPathArg) $(_crossBuildPropertyArg)
         - ${{ parameters.variables }}
 
       dependsOn:
diff --git a/eng/pipelines/mono/templates/build-job.yml b/eng/pipelines/mono/templates/build-job.yml
index e554e749a1c83c..d23bfded5a4e8f 100644
--- a/eng/pipelines/mono/templates/build-job.yml
+++ b/eng/pipelines/mono/templates/build-job.yml
@@ -67,9 +67,6 @@ jobs:
         value: /p:OutputRid=linux-musl-${{ parameters.archType }}
       - name: _PortableBuild
         value: true
-    - ${{ if eq(parameters.osGroup, 'iOS') }}:
-      - name: osOverride
-        value: -os iOS
     - ${{ parameters.variables }}
 
     steps:
@@ -78,7 +75,7 @@ jobs:
     # Linux builds use docker images with dependencies preinstalled,
     # and FreeBSD builds use a build agent with dependencies
     # preinstalled, so we only need this step for OSX and Windows.
-    - ${{ if in(parameters.osGroup, 'OSX', 'iOS') }}:
+    - ${{ if eq(parameters.osGroup, 'OSX') }}:
       - script: sh $(Build.SourcesDirectory)/eng/install-native-dependencies.sh $(osGroup)
         displayName: Install native dependencies
     - ${{ if eq(parameters.osGroup, 'Windows_NT') }}:
@@ -88,10 +85,10 @@ jobs:
 
     # Build
     - ${{ if ne(parameters.osGroup, 'Windows_NT') }}:
-      - script: ./mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) $(osOverride) -ci /p:MonoEnableLLVM=${{ parameters.llvm }}
+      - script: ./mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) -ci /p:MonoEnableLLVM=${{ parameters.llvm }}
         displayName: Build product
     - ${{ if eq(parameters.osGroup, 'Windows_NT') }}:
-      - script: mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) $(osOverride) -ci /p:MonoEnableLLVM=${{ parameters.llvm }}
+      - script: mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) -ci /p:MonoEnableLLVM=${{ parameters.llvm }}
         displayName: Build product
 
     # Publish product output directory for consumption by tests.
@@ -107,10 +104,10 @@ jobs:
 
     # Build packages
     - ${{ if and(ne(parameters.llvm, true), ne(parameters.osGroup, 'Windows_NT')) }}:
-      - script: ./mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) $(osOverride) -ci $(officialBuildIdArg) /p:MonoEnableLLVM=${{ parameters.llvm }} -pack $(OutputRidArg)
+      - script: ./mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) -ci $(officialBuildIdArg) /p:MonoEnableLLVM=${{ parameters.llvm }} -pack $(OutputRidArg)
         displayName: Build nupkg
     - ${{ if and(ne(parameters.llvm, true), eq(parameters.osGroup, 'Windows_NT')) }}:
-      - script: mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) $(osOverride) -ci $(officialBuildIdArg) /p:MonoEnableLLVM=${{ parameters.llvm }} -pack $(OutputRidArg)
+      - script: mono$(scriptExt) -configuration $(buildConfig) -arch $(archType) -ci $(officialBuildIdArg) /p:MonoEnableLLVM=${{ parameters.llvm }} -pack $(OutputRidArg)
         displayName: Build nupkg
 
     # Save packages using the prepare-signed-artifacts format.
diff --git a/eng/pipelines/mono/templates/xplat-job.yml b/eng/pipelines/mono/templates/xplat-job.yml
index 2cd61dc7e7f3e4..8d7465d7f88453 100644
--- a/eng/pipelines/mono/templates/xplat-job.yml
+++ b/eng/pipelines/mono/templates/xplat-job.yml
@@ -56,7 +56,7 @@ jobs:
       agentOs: Ubuntu
     ${{ if eq(parameters.osGroup, 'FreeBSD') }}:
       agentOs: FreeBSD
-    ${{ if in(parameters.osGroup, 'OSX', 'iOS') }}:
+    ${{ if eq(parameters.osGroup, 'OSX') }}:
       agentOs: MacOS
     ${{ if eq(parameters.osGroup, 'Windows_NT') }}:
       agentOs: Windows_NT
diff --git a/eng/pipelines/runtime-official.yml b/eng/pipelines/runtime-official.yml
index a49a4b1bbda73e..7619c2e533e1b8 100644
--- a/eng/pipelines/runtime-official.yml
+++ b/eng/pipelines/runtime-official.yml
@@ -69,9 +69,6 @@ stages:
       runtimeFlavor: mono
       buildConfig: release
       platforms:
-      - iOS_x64
-      - iOS_arm
-      - iOS_arm64
       - OSX_x64
       - Linux_x64
       - Linux_arm
@@ -107,22 +104,6 @@ stages:
         isOfficialBuild: ${{ variables.isOfficialBuild }}
         liveRuntimeBuildConfig: release
 
-  #
-  # Build libraries using live CoreLib from Mono
-  #
-  - template: /eng/pipelines/common/platform-matrix.yml
-    parameters:
-      jobTemplate: /eng/pipelines/libraries/build-job.yml
-      buildConfig: Release
-      runtimeFlavor: mono
-      platforms:
-      - iOS_x64
-      - iOS_arm
-      - iOS_arm64
-      jobParameters:
-        isOfficialBuild: ${{ variables.isOfficialBuild }}
-        liveRuntimeBuildConfig: release
-
   #
   # Build libraries AllConfigurations for packages
   #
diff --git a/eng/pipelines/runtime.yml b/eng/pipelines/runtime.yml
index d259efd65dc8a2..a1db9f327aedf6 100644
--- a/eng/pipelines/runtime.yml
+++ b/eng/pipelines/runtime.yml
@@ -226,9 +226,6 @@ jobs:
     runtimeFlavor: mono
     buildConfig: debug
     platforms:
-    - iOS_x64
-    - iOS_arm
-    - iOS_arm64
     - OSX_x64
     - Linux_x64
     - Linux_arm
@@ -256,9 +253,6 @@ jobs:
     runtimeFlavor: mono
     buildConfig: release
     platforms:
-    - iOS_x64
-    - iOS_arm
-    - iOS_arm64
     - OSX_x64
     - Linux_x64
     - Linux_arm
@@ -363,34 +357,6 @@ jobs:
     - Windows_NT_x64
     jobParameters:
       liveRuntimeBuildConfig: release
-
-#
-# Build libraries using Mono CoreLib only
-#
-- template: /eng/pipelines/common/platform-matrix.yml
-  parameters:
-    jobTemplate: /eng/pipelines/libraries/build-job.yml
-    buildConfig: Release
-    runtimeFlavor: mono
-    platforms:
-    - iOS_arm
-    - iOS_arm64
-    - iOS_x64
-    jobParameters:
-      liveRuntimeBuildConfig: release
-
-- template: /eng/pipelines/common/platform-matrix.yml
-  parameters:
-    jobTemplate: /eng/pipelines/libraries/build-job.yml
-    buildConfig: Debug
-    runtimeFlavor: mono
-    platforms:
-    - iOS_arm
-    - iOS_arm64
-    - iOS_x64
-    jobParameters:
-      liveRuntimeBuildConfig: debug
-
 #
 # Libraries Build that only run when libraries is changed
 #