diff --git a/.ci/manywheel/build_common.sh b/.ci/manywheel/build_common.sh
index f70b8df4149c..ec822b0cd4af 100644
--- a/.ci/manywheel/build_common.sh
+++ b/.ci/manywheel/build_common.sh
@@ -31,6 +31,7 @@ elif [[ "$OS_NAME" == *"Ubuntu"* ]]; then
     # Comment out nvidia repositories to prevent them from getting apt-get updated, see https://github.com/pytorch/pytorch/issues/74968
     # shellcheck disable=SC2046
     sed -i 's/.*nvidia.*/# &/' $(find /etc/apt/ -type f -name "*.list")
+
     retry apt-get update
     retry apt-get -y install zip openssl
 else
@@ -97,7 +98,6 @@ if [[ -z "$PYTORCH_ROOT" ]]; then
     exit 1
 fi
 pushd "$PYTORCH_ROOT"
-retry pip install -q cmake
 python setup.py clean
 retry pip install -qr requirements.txt
 case ${DESIRED_PYTHON} in
diff --git a/.ci/manywheel/build_libtorch.sh b/.ci/manywheel/build_libtorch.sh
index e9ab620475d1..8f70210dd5b6 100644
--- a/.ci/manywheel/build_libtorch.sh
+++ b/.ci/manywheel/build_libtorch.sh
@@ -92,7 +92,6 @@ if [[ -z "$PYTORCH_ROOT" ]]; then
     exit 1
 fi
 pushd "$PYTORCH_ROOT"
-retry pip install -q cmake
 python setup.py clean
 retry pip install -qr requirements.txt
 retry pip install -q numpy==2.0.1
diff --git a/.ci/pytorch/windows/arm64/build_libtorch.bat b/.ci/pytorch/windows/arm64/build_libtorch.bat
index 16df8fec70b6..1ac14ff69773 100644
--- a/.ci/pytorch/windows/arm64/build_libtorch.bat
+++ b/.ci/pytorch/windows/arm64/build_libtorch.bat
@@ -2,8 +2,8 @@
 
 :: environment variables
 set CMAKE_BUILD_TYPE=%BUILD_TYPE%
-:: set CMAKE_C_COMPILER_LAUNCHER=sccache
-:: set CMAKE_CXX_COMPILER_LAUNCHER=sccache
+set CMAKE_C_COMPILER_LAUNCHER=sccache
+set CMAKE_CXX_COMPILER_LAUNCHER=sccache
 set libuv_ROOT=%DEPENDENCIES_DIR%\libuv\install
 set MSSdk=1
 if defined PYTORCH_BUILD_VERSION (
@@ -43,10 +43,9 @@ pip install -r requirements.txt
 set DISTUTILS_USE_SDK=1
 
 :: start sccache server and reset sccache stats
-:: disable sccache because of debug file bug
-:: sccache --start-server
-:: sccache --zero-stats
-:: sccache --show-stats
+sccache --start-server
+sccache --zero-stats
+sccache --show-stats
  
 :: Prepare the environment
 mkdir libtorch
@@ -99,4 +98,4 @@ rmdir /s /q libtorch
 if %errorlevel% neq 0 (
     echo "Failed on build_libtorch. (exitcode = %errorlevel%)"
     exit /b 1
-)
+)
\ No newline at end of file
diff --git a/.github/requirements/pip-requirements-macOS.txt b/.github/requirements/pip-requirements-macOS.txt
index dbed4174fb49..f32eb1784d52 100644
--- a/.github/requirements/pip-requirements-macOS.txt
+++ b/.github/requirements/pip-requirements-macOS.txt
@@ -1,5 +1,5 @@
 boto3==1.35.42
-cmake==3.27.*
+cmake==3.25.*
 expecttest==0.3.0
 fbscribelogger==0.1.7
 filelock==3.6.0
diff --git a/CMakeLists.txt b/CMakeLists.txt
index ec6e82a2ddd5..2b479073f3a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
 # cmake_policy(SET CMP0022 NEW) cmake_policy(SET CMP0023 NEW)
 
 # Use compiler ID "AppleClang" instead of "Clang" for XCode. Not setting this
@@ -6,7 +6,6 @@ cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
 # one is detected as "AppleClang".
 cmake_policy(SET CMP0010 NEW)
 cmake_policy(SET CMP0025 NEW)
-cmake_policy(SET CMP0126 OLD)
 
 # Enables CMake to set LTO on compilers other than Intel.
 cmake_policy(SET CMP0069 NEW)
diff --git a/aten/src/ATen/CMakeLists.txt b/aten/src/ATen/CMakeLists.txt
index becfcee442d1..7de393974472 100644
--- a/aten/src/ATen/CMakeLists.txt
+++ b/aten/src/ATen/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
 set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
 
 if(NOT MSVC)
diff --git a/aten/src/ATen/native/quantized/cpu/qnnpack/deps/clog/CMakeLists.txt b/aten/src/ATen/native/quantized/cpu/qnnpack/deps/clog/CMakeLists.txt
index 979af29f723d..af31056c4430 100644
--- a/aten/src/ATen/native/quantized/cpu/qnnpack/deps/clog/CMakeLists.txt
+++ b/aten/src/ATen/native/quantized/cpu/qnnpack/deps/clog/CMakeLists.txt
@@ -4,7 +4,7 @@
 # This source code is licensed under the BSD-style license found in the
 # LICENSE file in the root directory of this source tree.
 
-cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
 
 include(GNUInstallDirs)
 
diff --git a/c10/CMakeLists.txt b/c10/CMakeLists.txt
index 8e9d267352dd..f00c662e70e0 100644
--- a/c10/CMakeLists.txt
+++ b/c10/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
 project(c10 CXX)
 
 set(CMAKE_CXX_STANDARD 17 CACHE STRING "The C++ standard whose features are requested to build this target.")
diff --git a/cmake/ProtoBuf.cmake b/cmake/ProtoBuf.cmake
index 1c8fc865c9ae..4c436dcd6451 100644
--- a/cmake/ProtoBuf.cmake
+++ b/cmake/ProtoBuf.cmake
@@ -34,29 +34,6 @@ macro(custom_protobuf_find)
   set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
   if(MSVC)
-    foreach(
-      flag_var
-      CMAKE_C_FLAGS
-      CMAKE_C_FLAGS_DEBUG
-      CMAKE_C_FLAGS_RELEASE
-      CMAKE_C_FLAGS_MINSIZEREL
-      CMAKE_C_FLAGS_RELWITHDEBINFO
-      CMAKE_CXX_FLAGS
-      CMAKE_CXX_FLAGS_DEBUG
-      CMAKE_CXX_FLAGS_RELEASE
-      CMAKE_CXX_FLAGS_MINSIZEREL
-      CMAKE_CXX_FLAGS_RELWITHDEBINFO)
-      # Replace /Zi and /ZI with /Z7
-      if(MSVC_Z7_OVERRIDE)
-        if(${flag_var} MATCHES "/Z[iI]")
-          string(REGEX REPLACE "/Z[iI]" "/Z7" ${flag_var} "${${flag_var}}")
-        endif()
-        if(${flag_var} MATCHES "[-]Zi")
-          string(REGEX REPLACE "[-Zi]" "/Z7" ${flag_var} "${${flag_var}}")
-        endif()
-      endif(MSVC_Z7_OVERRIDE)
-    endforeach(flag_var)
-
     foreach(flag_var
         CMAKE_C_FLAGS CMAKE_C_FLAGS_RELEASE CMAKE_C_FLAGS_MINSIZEREL
         CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_RELEASE CMAKE_CXX_FLAGS_MINSIZEREL)
@@ -64,24 +41,15 @@ macro(custom_protobuf_find)
         string(REGEX REPLACE "/Z[iI7]" "" ${flag_var} "${${flag_var}}")
       endif()
     endforeach(flag_var)
-
-    foreach(
-      flag_var
-      CMAKE_SHARED_LINKER_FLAGS_RELWITHDEBINFO
-      CMAKE_STATIC_LINKER_FLAGS_RELWITHDEBINFO
-      CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO
-      CMAKE_MODULE_LINKER_FLAGS_RELWITHDEBINFO
-      CMAKE_SHARED_LINKER_FLAGS_DEBUG
-      CMAKE_STATIC_LINKER_FLAGS_DEBUG
-      CMAKE_EXE_LINKER_FLAGS_DEBUG
-      CMAKE_MODULE_LINKER_FLAGS_DEBUG)
-      # Switch off incremental linking in debug/relwithdebinfo builds
-      if(${flag_var} MATCHES "/INCREMENTAL" AND NOT ${flag_var} MATCHES
-                                                "/INCREMENTAL:NO")
-        string(REGEX REPLACE "/INCREMENTAL" "/INCREMENTAL:NO" ${flag_var}
-                             "${${flag_var}}")
-      endif()
-    endforeach(flag_var)
+    if(MSVC_Z7_OVERRIDE)
+      foreach(flag_var
+          CMAKE_C_FLAGS_DEBUG CMAKE_C_FLAGS_RELWITHDEBINFO
+          CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELWITHDEBINFO)
+        if(${flag_var} MATCHES "/Z[iI]")
+          string(REGEX REPLACE "/Z[iI]" "/Z7" ${flag_var} "${${flag_var}}")
+        endif()
+      endforeach(flag_var)
+    endif(MSVC_Z7_OVERRIDE)
   endif(MSVC)
 
   if(CMAKE_VERSION VERSION_GREATER_EQUAL "4.0.0")
diff --git a/test/edge/CMakeLists.txt b/test/edge/CMakeLists.txt
index 1d7c8852fb50..985b77202485 100644
--- a/test/edge/CMakeLists.txt
+++ b/test/edge/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.18)
+cmake_minimum_required(VERSION 3.15)
 
 set(TORCH_ROOT ${CMAKE_CURRENT_LIST_DIR}/../..)
 set(TEST_ROOT ${TORCH_ROOT}/test/edge)
diff --git a/tools/setup_helpers/cmake.py b/tools/setup_helpers/cmake.py
index 678ba7ab207c..1fd7377cb07d 100644
--- a/tools/setup_helpers/cmake.py
+++ b/tools/setup_helpers/cmake.py
@@ -60,15 +60,12 @@ class CMake:
         cmake3_version = CMake._get_version(which("cmake3"))
         cmake_version = CMake._get_version(which("cmake"))
 
-        _cmake_min_version = LooseVersion("3.27.0")
+        _cmake_min_version = LooseVersion("3.18.0")
         if all(
             ver is None or ver < _cmake_min_version
             for ver in [cmake_version, cmake3_version]
         ):
-            raise RuntimeError(
-                "no cmake or cmake3 with version >= 3.27.0 found:"
-                + str([cmake_version, cmake3_version])
-            )
+            raise RuntimeError("no cmake or cmake3 with version >= 3.18.0 found")
 
         if cmake3_version is None:
             cmake_command = "cmake"
diff --git a/torch/CMakeLists.txt b/torch/CMakeLists.txt
index b07ba2a2d359..0da483c09743 100644
--- a/torch/CMakeLists.txt
+++ b/torch/CMakeLists.txt
@@ -2,7 +2,7 @@
 # Now it only builds the Torch python bindings.
 
 if(NOT CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO)
-  cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+  cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
   project(torch CXX C)
   find_package(torch REQUIRED)
   option(USE_CUDA "Use CUDA" ON)
diff --git a/torch/_inductor/cpp_builder.py b/torch/_inductor/cpp_builder.py
index 29f95df11e0b..20a7c77c9e9b 100644
--- a/torch/_inductor/cpp_builder.py
+++ b/torch/_inductor/cpp_builder.py
@@ -1729,7 +1729,7 @@ class CppBuilder:
         definitions = " ".join(self._build_option.get_definitions())
         contents = textwrap.dedent(
             f"""
-            cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+            cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
             project(aoti_model LANGUAGES CXX)
             set(CMAKE_CXX_STANDARD 17)
 
diff --git a/torch/lib/libshm/CMakeLists.txt b/torch/lib/libshm/CMakeLists.txt
index c3cd26fea7bf..8a7329ddab77 100644
--- a/torch/lib/libshm/CMakeLists.txt
+++ b/torch/lib/libshm/CMakeLists.txt
@@ -1,5 +1,5 @@
 project(libshm C CXX)
-cmake_minimum_required(VERSION 3.27 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
 
 set(TORCH_ROOT ${CMAKE_CURRENT_LIST_DIR}/../../../)