A Petri net based optimal control policy is proposed for the check of behavioral incompatibility in web services composition.According to a real case of multiple services interaction

this paper presents a formalized definition of controlled service composition

and the reduced state reachability graph of service composition net is given according to the reduce rules

thus the deadlock states and the deadlock-free states are identified.With the maximally permissive feedback control strategy developed

the appropriate control place and arc are appended in the key transition which can lead to deadlock states.Thus the appropriate optimal controller is developed

the proposed approach is verified.In addition

for the behavioral incompatibility case

a policy of appending optimal controller is presented.It is proved that our policy can be a good solution.Finally

the proposed controller is transformed as the activity of BPEL.