diff --git a/Web/Python/vtkmodules/web/utils.py b/Web/Python/vtkmodules/web/utils.py
index 24c0b77524e0cb44df7893468629919eae47eaf5..19925ef6ced3e93606e793343e7f79b9a027b3fa 100644
--- a/Web/Python/vtkmodules/web/utils.py
+++ b/Web/Python/vtkmodules/web/utils.py
@@ -1,5 +1,10 @@
+try:
+    import numpy as np
+except ImportError:
+    raise RuntimeError("This module depends on the numpy module. Please make\
+sure that it is installed properly.")
+
 import base64
-import numpy as np
 
 from vtkmodules.util.numpy_support import vtk_to_numpy
 from vtkmodules.vtkFiltersGeometry import vtkDataSetSurfaceFilter