diff --git a/Mesh_3/examples/Mesh_3/CMakeLists.txt b/Mesh_3/examples/Mesh_3/CMakeLists.txt
index da5d7e073ce..f7acf9c435a 100644
--- a/Mesh_3/examples/Mesh_3/CMakeLists.txt
+++ b/Mesh_3/examples/Mesh_3/CMakeLists.txt
@@ -62,9 +62,9 @@ if ( CGAL_FOUND )
    create_single_source_cgal_program( "mesh_polyhedral_domain.cpp" )
     create_single_source_cgal_program( "mesh_polyhedral_domain_with_features.cpp" )
     if( WITH_CGAL_ImageIO )
-      create_single_source_cgal_program( "mesh_optimization_example.cpp" )
-      create_single_source_cgal_program( "mesh_optimization_lloyd_example.cpp" )
       if( CGAL_ImageIO_USE_ZLIB )
+        create_single_source_cgal_program( "mesh_optimization_example.cpp" )
+        create_single_source_cgal_program( "mesh_optimization_lloyd_example.cpp" )
         create_single_source_cgal_program( "mesh_3D_image.cpp" )
         create_single_source_cgal_program( "mesh_3D_image_variable_size.cpp" )
       else()