diff --git a/cmake/external/protobuf.cmake b/cmake/external/protobuf.cmake
index c0cf2719f9a7b3ae6be5cefffa3dbd2c3f712e82..613614c0e3d42fac4147f78edbc1bd6d62847419 100644
--- a/cmake/external/protobuf.cmake
+++ b/cmake/external/protobuf.cmake
@@ -54,6 +54,7 @@ ExternalProject_Add(
   CONFIGURE_COMMAND
     ${CMAKE_COMMAND} ${PROTOBUF_SOURCES_DIR}/src/protobuf/cmake
     -Dprotobuf_BUILD_TESTS=OFF
+    -DZLIB_ROOT:FILEPATH=${ZLIB_ROOT}
     -DCMAKE_POSITION_INDEPENDENT_CODE=ON
     -DCMAKE_BUILD_TYPE=Release
     -DCMAKE_INSTALL_PREFIX=${PROTOBUF_INSTALL_DIR}