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信息物理系统(cyber-physical system,CPS)需要提供软件和硬件的无缝协调,满足系统的动态响应需求,实时任务准确的调度对CPS至关重要.事实上,由于各种原因,任务发生时间往往是不确定的.针对CPS时间不确定性导致的无法确定任务调度顺序的问题,首先利用剪枝简化发生时间不确定任务流,对所有简化后的任务流组合序列求解执行概率,确定任务流初始执行顺序;然后根据任务截止时间和空闲时间分派任务优先级;最后基于任务流初始执行顺序结合任务优先级,提出了一种动态优先级的面向CPS时间不确定任务流抢占调度算法.仿真实验结果证明,该算法能较地好保证系统调度任务的准确性和系统执行效率.“,”Cyber-physical system (CPS) needs to provide seamless coordination of software and hardware to meet the dy-namic response requirements of the system. Indeed, accurate scheduling of real-time tasks is critical to CPS. How-ever, the time of the task is uncertain because of a variety of reasons, causing uncertainty on the time tasks in the CPS. First, we simplified the uncertain-time task flow by using the pruning algorithm;then, we determined the ex-ecution probability of all the simplified task flow combination sequences, and we provided the initial task flow exe-cution order. Then, we proposed a dynamic priority scheduling algorithm for uncertain-time task flow on CPS, which take into account the task deadline and idle time dispatching task priority and is based on the initial execu-tion sequence of task flow combined with the task priority. The experimental results show that the algorithm can guarantee a better accuracy of the system scheduling tasks and the system execution efficiency.