The pervasive computing environment is transparent for users. In order to simplify the interaction between users and the environment, this paper presents a goal-driven approach of service composition. A task-oriented semantic representation model of Web services is built and based on this model goal-driven service composition is performed dynamically to achieve user’s goal. A simulated application scenario is described and the process of task definition and service composition according to the scenario are discussed in this paper. This approach simplifies the interaction between users and pervasive computing environment and improves the flexibility of service cooperation and composition in the environment.