The work aims to analyze and simulate the kinematics of the 3-CRS-S parallel mechanism to verify whether the mechanism has excellent kinematic performance. The modified Kutzbach-Grübler formula was used to calculate the degrees of freedom of the mechanism. The forward and inverse solutions of the 3-CRS-S parallel mechanism were analyzed by D-H method and particle swarm optimization (PSO) of numerical algorithm respectively. Adams software was used to analyze the angle and angular velocity of the 3-CRS-S parallel mechanism. The inverse and positive solutions of the mechanism, as well as the simulated angle and angular velocity images were obtained. The image curves showed regular and periodic changes, and there were no sudden changes or breakpoints in the curves, and the range of change was stable. It can be obtained that the mechanism runs smoothly in motion and has good kinematic performance. It has a broad application prospect in automated packaging machinery.