Post WIMP (i,e Windows．Icons．Menus and Pointer)interface as the next generation user in terrace has suhstantial differences from WIMP Interfaee．which has been the dominont paradigm of human compu rer interaction for decades Post-WIMP interface providese more natural and efficient interaction by utilizing theadvanced interactive technology，such as virtual reality．voice technology．gesture interaction and so on How-ever，it is proved to be more difficult to be constructed In order to build post WIMP interface effectively．it is abetter way to specify the interaction at an abstract level without concerning the details of the implementation he- fore construction In this paper-the fundamental attributes of post-WIMP interface fire discussed The most dis-tinguished property of post WIMP interface is the hybrid interaction．which-ns the continuous interaetlonblending with discrete interaction The post-WIMP interface is analyzed from the point of view of hybrid system，which can give more accurate and strlet analysis for post-WIMP interface Post-WIMP interface can be modeledas a set of cooperadng hybrid automata which are special for hybrid 8yst~nl Hybrid automata are used to modelpost WlMP interface A semi formal specification language LEAFF is designed based 0n hybrid au…aton forspecifying post-WIMP interface by the combination of the text-based specification and graph-based specification，sad it can clarify the control and temporal relationships in post-WIMP interface Two typical instances，objectmanipulationin virtual reality and peninteraction，are specified byLEAFF Someissues andthefuture work are also discussed，such as the specification of paralid issues in post WIMP interaction．verification of interactionand specification based interface construction The modeling technology presented in this paper ought to be useful to the research and development of post-WIMP Imerfaee