Objective: To solve the problems of large rigid impact and poor motion stability of parallel robot in the process of picking and placing canned food. Methods: Based on the architecture of high-speed parallel robot, a trajectory planning method was proposed for trajectory optimization of end effector of high-speed parallel robot. A multi constraint, multi-objective and nonlinear trajectory optimization model was established and solved by an improved gravity search algorithm. The feasibility of the proposed method was verified by simulation. Results: Compared with the planned method, the proposed method can complete the task in the shortest time of 0.169 1 s. Conclusion: The planning method solves the problems of large rigid impact and poor motion stability in the picking and placing process of traditional parallel robot, and has certain practical value.