Abstract: This paper proposes a Petri net based failure mode for embedded system and its analysis according to their characteristics. Petri nets are used as the formal description language for embedded systems, and use it to describe the basic elements of embedded system, such as, task, resource, sensor, actuator. We formally model the basic relationship between tasks, device and task interaction, and composition rules are used to dynamically integrate these models into a failure model of embedded system. The correctness of constructed model is analyzed based on the operation characteristics and the state space of the model. Finally, a specific example of verification process simulation of embedded system illustrates the feasibility of the method.