Aimed at the chattering problem in numerical control (NC) machining process especially during machining the thinwalled components, by taking multi-farmed parts as the objective, the model of chatter prediction based on NC physical simulation in machining Ti alloy thin-walled components was established. The predication of chattering was realized and solved right in the primary stage of technical preparation of the Ti alloy components. Firstly, by the combined method of experiment and simulation, the stability domain of chatter of technical system was obtained, and parameters in stability domain were optimized. Secondly, by establishing finite element model (FEM), the modal of the components was analyzed, the dynamic characteristics of the machining process of components were obtained and optimal tool path was determined. Finally, the cutting process was simulated for the components by using NC physical simulation software, so as to predict the happening of chatter during cutting process. The results show that through this kind of technique, the machining process can be effectively and intuitively followed, and improved machining stability of the thin-walled components.