diff --git a/build_files/cmake/platform/platform_apple.cmake b/build_files/cmake/platform/platform_apple.cmake
index 9ba499deeb5..b160ca2653e 100644
--- a/build_files/cmake/platform/platform_apple.cmake
+++ b/build_files/cmake/platform/platform_apple.cmake
@@ -243,7 +243,7 @@ endif()
 
 if(WITH_BOOST)
   set(Boost_NO_BOOST_CMAKE ON)
-  set(BOOST_ROOT ${LIBDIR}/boost)
+  set(Boost_ROOT ${LIBDIR}/boost)
   set(Boost_NO_SYSTEM_PATHS ON)
   set(_boost_FIND_COMPONENTS date_time filesystem regex system thread wave)
   if(WITH_INTERNATIONAL)
diff --git a/build_files/cmake/platform/platform_unix.cmake b/build_files/cmake/platform/platform_unix.cmake
index 6695411e1c6..d8bed47f869 100644
--- a/build_files/cmake/platform/platform_unix.cmake
+++ b/build_files/cmake/platform/platform_unix.cmake
@@ -77,7 +77,7 @@ if(DEFINED LIBDIR)
     set(WITH_OPENMP_STATIC ON)
   endif()
   set(Boost_NO_BOOST_CMAKE ON)
-  set(BOOST_ROOT ${LIBDIR}/boost)
+  set(Boost_ROOT ${LIBDIR}/boost)
   set(BOOST_LIBRARYDIR ${LIBDIR}/boost/lib)
   set(Boost_NO_SYSTEM_PATHS ON)
   set(OPENEXR_ROOT_DIR ${LIBDIR}/openexr)