diff --git a/.github/workflows/llvm.yml b/.github/workflows/llvm.yml
index d8df01d13090..d803b5de4bb2 100644
--- a/.github/workflows/llvm.yml
+++ b/.github/workflows/llvm.yml
@@ -26,6 +26,8 @@ jobs:
             llvm_ubuntu_version: "22.04"
           - llvm_version: "17.0.6"
             llvm_ubuntu_version: "22.04"
+          - llvm_version: "18.1.4"
+            llvm_ubuntu_version: "18.04"
     name: "LLVM ${{ matrix.llvm_version }}"
     steps:
       - name: Checkout Crystal source