The influence of the uncertain or malicious service nodes on the Web service composition (WSC) performance is generally fatal in the Internet, so the problems of services selecting for WSC can not be completely solved by the perspective of performance. In the paper, the two-tier model of reputation computing, which describes the credibility evolution mechanism of the inter-entity relations in the course of services composition, has been proposed. A trust reputation computing mode is builded through interactive services composition submitted by the parties, then an intuitive reputation evaluation model is formed through the direct or indirect interaction between services entities. On that basis, the services scheduling algorithm based on trust reputation evolution model has been proposed, which can effectively inhibit the interference of fraudulent services entity and reduce the influence of low-quality services in WSC. Experimental results show that the method proposed in the paper is more superior in credibility and security, comparing to the traditional services scheduling methods.