Due to the complexity of freeform surface machining, multi- Axes machine tools are widely used to increase the precision of surface machining. There are needs for the user, designer and manufacturer of machine tool constructing the multi- Axis machine tools with various configurations by the virtual reality technique. The damage of multi- Axis machine tool due to collision can be prevented by virtual machine tool simulation. The machining information, such as the machining time, machining accuracy and the NC codes that cause collisions, can be obtained before actual machining. Most of the previous research of postprocessor concentrated on the orthogonal and single configurations. This paper aims at developing an automated universal postprocessor for both orthogonal and nonorthogonal configurations. The configuration information of machine tools and modified D-H notation is employed to develop the postprocessor of multi- Axes machine tools. The user interface of the system has been implemented and displayed by OpenGL. A case study is given to demonstrate the construction procedure of virtual machine tool. Finally, the NC program converted from the developed postprocessor has been verified with commercial software.