Abstract: In this.papes.the sufficient and necessary conditions for deadlock avoidance in flexible manufactu ring systems and the corresponding control law are presented by using the colored ROPN developed in partI.This control law is a policy of dynamic resource allocation. When a resource is free the control law determine whether the resource can be allocated to a job and which job should obtain the resource first if it can,so as to avoid deadlock.This control law maximizes the resource utilization with deadlock-free operation in the system.