diff --git a/CMakeLists.txt b/CMakeLists.txt
index e8ea828dd2a25f5f47b03e92ae86e083d4425dc9..49334279f6dc88c0d35fec43daf80e3cbe65760c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -137,7 +137,7 @@ include(external/openblas)  # download, build, install openblas
 include(external/mkldnn)    # download, build, install mkldnn
 include(external/swig)      # download, build, install swig
 include(external/warpctc)   # download, build, install warpctc
-include(external/boost)     # download, build, install boost
+include(external/boost)     # download boost
 include(external/any)       # download libn::any
 include(external/eigen)     # download eigen3
 include(external/pybind11)  # download pybind11
diff --git a/cmake/external/boost.cmake b/cmake/external/boost.cmake
index c70d83b3f4bb24740ed67b4e2f98a3ced26d1648..dbc676bdac30e0d730206c17a1912d49d4f896eb 100644
--- a/cmake/external/boost.cmake
+++ b/cmake/external/boost.cmake
@@ -21,6 +21,7 @@ set(BOOST_URL           "http://sourceforge.net/projects/boost/files/boost/${BOO
 set(BOOST_SOURCES_DIR ${THIRD_PARTY_PATH}/boost)
 set(BOOST_DOWNLOAD_DIR  "${BOOST_SOURCES_DIR}/src/${BOOST_PROJECT}")
 set(BOOST_INCLUDE_DIR "${BOOST_DOWNLOAD_DIR}/${BOOST_TAR}" CACHE PATH "boost include directory." FORCE)
+set_directory_properties(PROPERTIES CLEAN_NO_CUSTOM 1)
 
 include_directories(${BOOST_INCLUDE_DIR})