diff --git a/ci/travis_osx_install b/ci/travis_osx_install
index 0386e6d7ab..6974147109 100755
--- a/ci/travis_osx_install
+++ b/ci/travis_osx_install
@@ -2,6 +2,6 @@
 
 set -x
 
-brew install llvm@5
-brew outdated llvm@5 || brew upgrade llvm@5
+brew install llvm@6
+brew outdated llvm@6 || brew upgrade llvm@6
 
diff --git a/ci/travis_osx_script b/ci/travis_osx_script
index db3992aa8e..56cf45cd5f 100755
--- a/ci/travis_osx_script
+++ b/ci/travis_osx_script
@@ -5,7 +5,7 @@ set -e
 
 mkdir build
 cd build
-cmake .. -DCMAKE_PREFIX_PATH=/usr/local/opt/llvm@5/ -DCMAKE_INSTALL_PREFIX=$(pwd)
+cmake .. -DCMAKE_PREFIX_PATH=/usr/local/opt/llvm@6/ -DCMAKE_INSTALL_PREFIX=$(pwd)
 make VERBOSE=1
 make install