The software prototyping approach was proposed as a new paradigm to remedy some drawbacks in traditional life-cycle model. The challenge is to develop a suitableintegrated prototyping environment which enables the developer to specify and construct aprototype easily. Therefore, the authors designed and implemented an object-oriented integrated software prototyping environment (SPE) on VAX Ⅱ/GPX workstation. This paper presented the design, the implementation and the main characteristics of SPE. The users and designers can draw a precise and correct requirement specification and verify the possibility of the application system design after running a prototype.