A new parallel mechanism with three degrees of freedom (3DOF) was put forward, screw theory was applied to analyse the mechanism principle of the parallel mechanism and to calculate the degree of freedom (DOF) of the mechanism. The multibody system dynamics model of the parallel mechanism was established based on the multirigidbody system dynamics theory, and kinematics, inverse kinematics and dynamics simulation analysis was carried out. The results show that in the designed model and dimensions, there is a nonlinear relation between the input and output of the mechanism. Under control the output of the Z axis direction in certain circumstances, the maximum angle of output in X direction is -15 degrees, and the maximum angle of output in Y direction is -17 degrees. The motion curve of velocity and acceleration of the mechanism is gentle, without obvious rigid impact in the mechanism.