Abstract: There is no flexible and dynamic service composition method for composing the complex service from the simple basic services in pervasive computing. A dynamic service composition method based on semantic interface matching is introduced. It gives system framework for the elementary service description schema based on semantic,the composition service description schema,the arithmetic for creating the instances of composition service,and the control method for service. This method also verifies the framework by instance implementation. It is very useful for effectively using the system resource and reducing the complexity designing and implementing the services by composing the complex services from the elementary service.