A cyber physical system (CPS) is composed of plant, sensors, actuators, supervisor and communication networks. The use of communication networks increases the vulnerability of CPS to cyber attacks. In this paper, we summarize the related research work of tackling the attack issues of CPS based on the framework of discrete event systems. First, we give a brief introduction to CPS. Next, we classify attacks in CPS. Finally, the various work on the design of attack strategies, the detection and defense of attack and the design of robustness supervisor for CPS vulnerable to attacks are introduced.