The dynamic performance of 4-SPS/CU parallel mechanism considering spherical joint with clearance is developed, and the 3-D wear property of the socket based on the Archard's wear model. Firstly, the kinematics model of spherical joint with clearance is established, and the updated procedure pertaining to the contact mechanics and wear state is explained via a flow chart. An improved contact force model is proposed by Flores et al. contact force model through a revised contact stiffness coefficient. The normal and tangential contact forces between ball and socket are calculated using the improved contact force model and a modified Coulomb friction model. Secondly, the dynamic model of the parallel mechanism considering spherical joint with clearance is formulated based on the multibody equations of motion. In order to obtain the 3-D wear property of spherical joint with clearance, the contact force is decomposed into three components in the global coordinate system. The three components of sliding distance are computed based on the 3-D revolute property of the parallel mechanism. Finally, the contact pressures in three different directions are calculated by the corresponding contact force and approximate contact area components for the sake of predicting the 3-D wear depth of socket based on the Archard's wear model. The simulation results show that the wear depth in different direction along the socket surface is non-uniform, which affects the performance of 4-SPS/CU parallel mechanism.