The increase of image data presents a serious challenge for the encryption algorithm in video surveillance.Complex encryption and decryption algorithm will increase the cost of calculation,which influences real-time performance of video transmission.In this paper,according to encryption and decryption requirements of the video,optical encryption and decryption is proposed in the field of video surveillance,and optical encryption and decryption system was designed based on double random phase encoding.The calculation speed of encryption and decryption is equal to the speed of light.Therefore,the spent time is almost equal to zero.The optical system will generate important value with the rapid popularity of high definition video and have broad application prospect in the domain of military encryption and decryption.