Aiming at the problem of multi-agent path planning in dynamic environments, we propose an improved dynamic path planning method by combining the ant colony algorithm and fireworks algorithm. This method accelerates the iteration speed of the algorithm by adapting the pheromone intensity value and the pheromone reduction factor, and uses the fireworks algorithm to solve the deadlock problem in the path planning process and avoid falling into a local optimum. In the process of multi-agent dynamic collision avoidance, corresponding collision avoidance strategies are made according to whether the motion trajectory between dynamic obstacles and multiagent intersects, and the path collision function is used to solve the multi-agent frontal collision problem. Simulation results show that the proposed algorithm is superior to the traditional ant colony algorithm. It can effectively solve the collision problem in multiagent path planning, and quickly find the optimal collision-free path.