diff --git a/External/CMakeLists.txt b/External/CMakeLists.txt
index d9e071e8..4d969013 100644
--- a/External/CMakeLists.txt
+++ b/External/CMakeLists.txt
@@ -36,6 +36,7 @@ endif()
 
 if(ENABLE_OPT AND NOT TARGET SPIRV-Tools-opt)
     if(IS_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/spirv-tools)
+        set(SPIRV_SKIP_TESTS ON CACHE BOOL "Skip building SPIRV-Tools tests")
         add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/spirv-tools spirv-tools)
     endif()
 endif()