Chatter, stick-slip, and other nonlinear complex dynamic Phenomena are investigated in the two degrees of freedom chatter system with dry friction. Dynamic model combined with nonlinear coefficient of friction is established. Dynamic characteristics are quantitative researched by using Runge-Kutta-Fehlberg(RK45) to obtain the curves of chatter amplitude changing with brake speed, stiffness k2 and damping c2 especially. The results show that, the flutter phenomena can be found when the brake moves at a low speed. The intensity of chatter vibration can be effected by stiffness and damping in some degree, so reasonable parameters of the system can reduce chatter.