By analyzing the functional requirements of the geometric simulation environment, the structure of the geometric simulation environment was designed.An eightaxis boring and milling machining center with fiveaxis linkage produced by a certain company was taken as the prototype, the geometric constraint relations and motion relation of the machine tool was analyzed,the machine tool model, control model and measurement analysis model were built, and the geometric simulation machining environment with all functions, characteristics and behaviors of the real machine tool system was established. The practical application shows that the established simulation environment can factually reflect the static and dynamic characteristics of machine tools; simulation measurement and analysis in this simulation environment can effectively ensure the machining quality of products and the safety of machine tools. The proposed geometry simulation environment construction method provides technical support and reference for constructing other multiaxis machining geometric simulation environments.