Abstract: The existing Web services integration systems have three major disadvantages, in order to improve these disadvantages, this study propose extend the traditional contract net model so as to improve its disadvantage in allocating tasks. In the extended model, the tendering tactic is developed based on creditworthiness of task acquaintance and the bid awarded tactic is advanced based on the fuzzy comprehensive evaluation. Hence, it not only guarantees the quality of task fulfillment but also solves the problem of excessive communication in the traditional contract net model.