在关键任务部门中 ,实时双系统的应用越来越广泛。如何保证高的可用度和高的响应时间是它们共同面临的问题。在本文中 ,全面论述了强实时双系统容错技术中的关键问题 ,包括系统结构定义、故障检测、状态切换。实际应用的结果表明 ,方案可以满足应用系统高可靠、强实时的需求 ,取得了良好的效果 In mission-critical departments, real-time dual-system applications are more and more widely used. How to ensure high availability and high response time are the common problems they face. In this paper, the key issues of fault-tolerant technology in real-time dual systems are comprehensively discussed, including the definition of system structure, fault detection and state switching. The practical application shows that the scheme can meet the needs of high reliability and strong real-time of application system and achieved good results