Based on the principle of binocular vision, a virtual assembly system of cyber-physical systems (CPS) in augmented reality environment was developed by using Unity3D game engine. The registration relationship between virtual model and real assembly unit was established by studying the fast location algorithm through identifying the feature marker points. The virtual assembly simulation was realized by fusing the projection image of virtual model and the real assembly image, and the real-time output was displayed by the video glasses. The experimental results show that the system meets the requirements of real-time CPS, stability and integration of information world and physical world.