To resolve some problems,such as small workspace,about the traditional parallel machine tools,a new kind of 5-axis serial-parallel machine tool is introduced,which has large workspace as well as good static and dynamic stiffness.Considering the strong coupling between position parameters and orientation parameters of the movable platform,the relationship between them is established.The numerical and analytic algorithms are adopted together to solve the inverse kinematics solution,and the bar length approaching algorithm is adopted in the forward kinematics solution without consideration of the additional initial position parameters.The solution method is verified to be correct through two samples,which is important to the analysis of control system of the machine tool.