Aiming at the safety analysis of complicated business process, its pervasion mechanism is expounded both from structure and evolvement. The course of its transfer, accumulation and release is depicted with frequency and penetrability of safety risk network node,which are caculated by maximun entropy model and grey relation entropy model. Finally, an applied case of flight line maintenance process is provided to illustrate the feasibility crisp path based on ant algorithm, and to verify the efficiency to find the process crisp nodes which become the proofs for the availability of process risk management.