In recent years, Web services had been widely used on the Internet. Thanks to the convenient communication technologies and their inexpensive cost, communications between organizations is much easier, and Web services have become a de-facto standard for organizations to provide information and services. There are two different perspectives to describe Web service composition: orchestration and choreography. Works that verify a choreography model so as to alleviating some correctness problem such as deadlock have also been proposed. However the verification of implementations based on a choreography model has not be addressed. In this thesis, we propose an approach to verify the conformance of a set of Web services to a given choreography model and prune some candidate Web services which do not comply with the choreography model to avoid discordance with the choreography model and run-time errors. The proposed approach is evaluated by simulating 10,000 execution sequences of composite Web services. The experimental results show that our proposed method improves the performance of success rate and space usage by pruning the unsuitable candidate Web services.