diff --git a/.github/workflows/be-ut-mac.yml b/.github/workflows/be-ut-mac.yml
index 4f3db038dbab83..e7edafe3eb8a6c 100644
--- a/.github/workflows/be-ut-mac.yml
+++ b/.github/workflows/be-ut-mac.yml
@@ -29,7 +29,7 @@ concurrency:
 jobs:
   run-ut:
     name: BE UT (macOS)
-    runs-on: macos-13
+    runs-on: macos-15-intel
     steps:
       - name: Checkout
         uses: actions/checkout@v3
@@ -44,6 +44,7 @@ jobs:
         with:
           filters: |
             be_changes:
+              - '.github/workflows/be-ut-mac.yml'
               - 'be/**'
               - 'gensrc/proto/**'
               - 'gensrc/thrift/**'
@@ -80,21 +81,48 @@ jobs:
             'openjdk@11'
             'maven'
             'node'
-            'llvm@16'
+            'llvm@18'
+            'libomp'
           )
           brew install "${cellars[@]}" || true
+          # The Intel runner exposes Homebrew's latest fmt from /usr/local/include,
+          # which can shadow the branch-pinned fmt shipped in the Doris thirdparty bundle.
+          brew unlink fmt || true
 
           pushd thirdparty
           branch="${{ github.base_ref }}"
+          case "$(uname -m)" in
+            arm64) asset="doris-thirdparty-prebuilt-darwin-arm64.tar.xz" ;;
+            x86_64) asset="doris-thirdparty-prebuilt-darwin-x86_64.tar.xz" ;;
+            *) echo "Unsupported macOS architecture: $(uname -m)" >&2; exit 1 ;;
+          esac
+          common_url="https://github.com/apache/doris-thirdparty/releases/download/automation/${asset}"
           if [[ -z "${branch}" ]] || [[ "${branch}" == 'master' ]]; then
-            curl -L https://github.com/apache/doris-thirdparty/releases/download/automation/doris-thirdparty-prebuilt-darwin-x86_64.tar.xz \
-              -o doris-thirdparty-prebuilt-darwin-x86_64.tar.xz
+            curl -fL "${common_url}" -o "${asset}"
           else
-            curl -L "https://github.com/apache/doris-thirdparty/releases/download/automation-${branch/branch-/}/doris-thirdparty-prebuilt-darwin-x86_64.tar.xz" \
-              -o doris-thirdparty-prebuilt-darwin-x86_64.tar.xz
+            branch_url="https://github.com/apache/doris-thirdparty/releases/download/automation-${branch/branch-/}/${asset}"
+            if ! curl -fL "${branch_url}" -o "${asset}"; then
+              echo "::warning::No branch-specific macOS thirdparty asset for ${branch}; using automation"
+              curl -fL "${common_url}" -o "${asset}"
+            fi
           fi
-          tar -xvf doris-thirdparty-prebuilt-darwin-x86_64.tar.xz
+          tar -xvf "${asset}"
           popd
 
-          export JAVA_HOME="${JAVA_HOME_17_X64%\/}"
+          export JAVA_HOME
+          JAVA_HOME="$(/usr/libexec/java_home -v 17)"
+
+          LLVM_PREFIX="$(brew --prefix llvm@18)"
+          export PATH="${LLVM_PREFIX}/bin:${PATH}"
+          export DORIS_CLANG_HOME="${LLVM_PREFIX}"
+          export CC="${LLVM_PREFIX}/bin/clang"
+          export CXX="${LLVM_PREFIX}/bin/clang++"
+
+          LIBOMP_PREFIX="$(brew --prefix libomp)"
+          export CPPFLAGS="-I${LIBOMP_PREFIX}/include ${CPPFLAGS:-}"
+          export CFLAGS="-I${LIBOMP_PREFIX}/include ${CFLAGS:-}"
+          export CXXFLAGS="-I${LIBOMP_PREFIX}/include ${CXXFLAGS:-}"
+          export LDFLAGS="-L${LIBOMP_PREFIX}/lib ${LDFLAGS:-}"
+          export EXTRA_CXX_FLAGS="-I${LIBOMP_PREFIX}/include ${EXTRA_CXX_FLAGS:-}"
+
           ./run-be-ut.sh --run -j "$(nproc)" --clean
diff --git a/be/CMakeLists.txt b/be/CMakeLists.txt
index 3d6fb25f7f1101..48d0ab71fc66cd 100644
--- a/be/CMakeLists.txt
+++ b/be/CMakeLists.txt
@@ -843,8 +843,11 @@ if (ENABLE_PCH)
     find_package(OpenMP QUIET)
     if (OpenMP_CXX_FOUND OR OpenMP_FOUND)
         if (DEFINED OpenMP_CXX_FLAGS AND NOT OpenMP_CXX_FLAGS STREQUAL "")
+            separate_arguments(OPENMP_CXX_FLAG_LIST NATIVE_COMMAND "${OpenMP_CXX_FLAGS}")
             # Apply the OpenMP flags to all C++ compilations so PCH and all TUs match.
-            add_compile_options($<$<COMPILE_LANGUAGE:CXX>:${OpenMP_CXX_FLAGS}>)
+            foreach(OPENMP_CXX_FLAG IN LISTS OPENMP_CXX_FLAG_LIST)
+                add_compile_options($<$<COMPILE_LANGUAGE:CXX>:${OPENMP_CXX_FLAG}>)
+            endforeach()
         endif()
         # Ensure final link includes the OpenMP runtime when needed.
         if (TARGET OpenMP::OpenMP_CXX)
@@ -864,7 +867,7 @@ if (ENABLE_PCH)
         target_link_libraries(pch PUBLIC OpenMP::OpenMP_CXX)
         # Also add flags explicitly to be robust if usage requirements don’t apply during PCH.
         if (DEFINED OpenMP_CXX_FLAGS AND NOT OpenMP_CXX_FLAGS STREQUAL "")
-            target_compile_options(pch PUBLIC ${OpenMP_CXX_FLAGS})
+            target_compile_options(pch PUBLIC ${OPENMP_CXX_FLAG_LIST})
         endif()
         # Copy usage requirements from the imported OpenMP target onto PCH.
         if (TARGET OpenMP::OpenMP_CXX)
@@ -883,7 +886,7 @@ if (ENABLE_PCH)
         endif()
     endif()
     if (COMPILER_CLANG)
-        target_compile_options(pch PRIVATE -Xclang -fno-pch-timestamp)
+        target_compile_options(pch PRIVATE "SHELL:-Xclang -fno-pch-timestamp")
     endif()
 endif()