Kinematics of parallel mechanism is the basic study of the dynamic characteristics and controlling system design, the computation of kinematics of parallel mechanism greatly influences the subsequent analysis of the kinematics and dynamic characteristics. Based on Euler transform method, and through analyzing 4UPS + UPU parallel mechanism kinematics, the position, velocity and acceleration of analytic expression and the Jacobian matrix and Hessian matrix can be got. By numerical simulation, we can get the motion of the driver branched variation of length, speed and acceleration under the given platform motion. Simulation results show that the drive branch length, velocity and acceleration curves are smooth transition, it’s beneficial to control the driver branched variation of length and to ensure the dynamic characteristics of institutions.