diff --git a/CMakeLists.txt b/CMakeLists.txt
index 56963182ad52729281c4950d974b726b8785e62a..4256d6972bcc1f24956830d90b354468c3ad714d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -166,7 +166,7 @@ mark_as_superbuild(${PROJECT_NAME}_USE_VRPN:BOOL)
 option(${PROJECT_NAME}_USE_RENDERING_VTK "Build with/out VTK rendering support" ON)
 mark_as_superbuild(${PROJECT_NAME}_USE_RENDERING_VTK:BOOL)
 
-if (${PROJECT_NAME}_USE_RENDERING_VTK AND ${PROJECT_NAME}_USE_VTK_OSMESA)
+if (NOT ${PROJECT_NAME}_USE_RENDERING_VTK AND ${PROJECT_NAME}_USE_VTK_OSMESA)
   message(FATAL_ERROR "Setting ${PROJECT_NAME}_USE_VTK_OSMESA ON is only supported when ${PROJECT_NAME}_USE_RENDERING_VTK is ON")
 endif()