An anti-counterfeiting means using phase-only CGH is presented in this paper. Two phase-only CGHs are made by decomposing the phase information into two parts. When single CGH is reconstructed, no information will be observed, while two alignment combined phase-only CGHs are reconstructed, the recorded information will be read out on the image plane. Any one of the CGH can act as the decoding key. Because the phase distribution on each CGH is a random one, it is very difficult to duplicate the identical decoding CGH.