In order to ensure the reliable execution of the functional safety of industrial control systems and effectively resist more and more serious cyber attacks, it is necessary to explore a technical solution suitable for industrial control systems to effectively ensure the compatibility of cyber security and functional security measures. Taking typical SIL3 and SL3 industrial control systems as examples, based on functional safety measures, cyber security measures are analyzed one by one, and potential contradictions between them are identified. Coordination solutions of functional safety and cyber security are given by combining event tree and risk analysis. Finally, integrated protective measures of functional safety and cyber security of industrial control systems are obtained.The results show that the cyber security measures determined by the coordination method are compatible with the original functional safety measures, and the coordination method can be used to guide the cyber security design of industrial control systems.