The parallel kinematics machine tool is based on the space of mechanism. It can achieve space complex motion, meet requirements of processing of multi-degree freedom, and can process complex parts. Because the design process of a parallel kinematics machine tool is quite complicated, there are limitations of the traditional design methods using experience and static researches. It is necessary to explore the related design theories and study the dynamic characteristics of the parallel kinematics machine tool. This study takes a 4-XPXUYYUX parallel kinematics machine tool as an example, develops the mathematical model of kinematics analysis by the coefficient method. The dynamic model is solved using Lagrange equation, which can provide the basis for other theoretical analysis. We develop a simulation model of parallel kinematics machine tool by the virtual prototype software-ADAMS, and analyze the dynamic of parallel kinematics machine tool. The dynamic characteristics of parallel kinematics machine tool are acquired. The system design of parallel kinematics machine tool is improved and optimized.