To promote the Model-Based software engineering development of user interfaces, this paper proposes a model driven development approach of complex user interface. The approach captures the process data in user interfaces by using an Extended odel. User interfaces are directly, abstractly depicted as objects, components and their cooperative relations in an Interaction Model. Their external visual presentation is customized in the Presentation Model in the name of UI Template. ueness of this research is a direct and leveled abstractive attack on complex user interface composition or description, rather than the elicitation from task models. Categories and Subject Descriptors D.2.1[Requirements/Specification]: Methodologies - Model Based User Interface; Representation - User Interface; D.2.2 [Design Tools and Techniques]: Computer-Aided Software Engineering (CASE) - Model Based User Interface Development Environment; General Terms Design, Experimentation, Theory Keywords Software Engine...