Abstract: It first introduces the concept of particle swarm optimization algorithm, and then analyzes and studies the optimization constraint model of agricultural robots from the mathematical model, boundary constraints and environmental constraints. It finally realizes the dynamic obstacle avoidance and path planning of agricultural robots. The simulation experiment showed that the agricultural robot can carry out the optimal obstacle avoidance path planning for the complex working environment, and the algorithm convergence speed was fast, which can meet the design requirements and prove that the system has certain feasibility.