diff --git a/src/Unittests/unittests_eigen3_type.cc b/src/Unittests/unittests_eigen3_type.cc
index 6d263220..b9f59a61 100644
--- a/src/Unittests/unittests_eigen3_type.cc
+++ b/src/Unittests/unittests_eigen3_type.cc
@@ -161,7 +161,7 @@ TEST_F(OpenMeshEigenTest, Test_Basic_setup) {
   mesh_.add_face(face_vhandles);
 
 
-  EXPECT_EQ(mesh_.n_faces(),2) << "Wrong number of faces";
+  EXPECT_EQ(mesh_.n_faces(),2u) << "Wrong number of faces";
 
 }