Abstract: A system architecture of 3D virtual machining environment is presented based on the analysis of characteristics of virtual manufacturing．Its main constituents include： component design supporting 3D modeling and simulation，modeling of virtual machining center based on its assembly model，NC code parser and simulation of machining process based on triangular faceted model of work-piece．Details of their implementation are illustrated．The prototype system of virtual machining environment has been developed to realize the integrated simulation of machining process of work-piece and to analyze the machinability of virtual prototype part．