Abstract: The focus of this paper lies on developing an immersive virtual maintenance simulation system to meet the demands of virtual maintainability analysis, virtual maintenance procedure validation and virtual maintenance training. This paper presents a framework for simulating maintenance in immersive virtual environments, and introduces the key techniques for prototype modeling and interaction. In prototype modeling, a concept of virtual maintenance prototype (VMP) is put forward, and its functions are realized by defining constrained-motions and interaction features of all parts of a VMP. In interaction, the main concern is on grasping and penetration handling. Finally, a sample is given on the establishment and validation of an immersive virtual maintenance simulation system based on Jack through the assembling and disassembling of a machine.