Spot welding is widely used in the modern industry, and task planning of welding is directly related to the improvement of manufacturing efficiency.When the path length is considered as the optimization objective, the path planning of the spot welding robot can be simplified as the optimization of the welding sequence that is the traveling salesman problem. Considering the traveling salesman problem is the NP complete problem and the discrete problem, the Levy-PSO algorithm is presented to obtain the optimal solution of the welding path through the study of the discrete Levy flight and the discrete PSO algorithm. The rationality and feasibility of the scheme are verified through the welding robot path planning simulation.