Researching on the maintenance scheduling strategy is important to improve the maintenance performance. Based on the analysis of resource conflict in the maintenance process, the resource scheduling strategy is studied, which includes task priority, resource assign rule, sharing resource of parallel task and cross maintenance. A model is constructed based on Petri net, which reflects the resource scheduling strategy in maintenance process by using transition enabling priority, inhibitory arc and transition enabling predicates. At last, a typical case is studied, which reflects the influence to maintenance index including equipment down time. The model provides a method to improve the effectiveness of maintenance scheduling strategy.