The study of the surface elastic properties of chemical vapor deposited (CVD) diamond films by means of the high resolution Brillouin spectroscopy reveals a clear difference in the elastic response between the nucleation face and the growth face, the second one being elastically stiffer. This information is relevant for the technological application of CVD diamond films in surface acoustic wave devices. This fact also implies the existence of elastic gradients in the CVD grown films. (C) 2005 American Institute of Physics.