diff --git a/CMakeLists.txt b/CMakeLists.txt
index f1dbfd2c01d6c6ea5d82711035504fc57724148f..a2075164663fbecd5653571f6996eee2f3c79c9e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -92,6 +92,9 @@ include(GridUtils)
 
 add_header_listing()
 make_dependent_modules_sys_included()
+if (EIGEN3_FOUND)
+  add_definitions("-isystem ${EIGEN3_INCLUDE_DIR}")
+endif (EIGEN3_FOUND)
 
 add_subdirectory(dune)
 add_subdirectory("cmake/modules")