The work aims to ensure that the picking, pre-cooling, storage, distribution and sales of litchi can be completed in a short time, so as to improve quality safety and freshness, and reduce logistics costs. With the four main factors like distribution vehicle transportation, cold chain energy consumption, litchi loss and time window penalty as study objects, the cost model of each factor was constructed and the cost optimal objective optimization function in the process of litchi cold chain logistics distribution was determined. The ant colony algorithm was used to solve the cost optimal objective function example in the process of litchi cold chain logistics distribution, so as to obtain the network optimization roadmap of litchi cold chain logistics distribution path. The experimental results showed that when the algorithm heuristic factor α=1, the expected heuristic factor β=4, the pheromone volatilization coefficient ρ=0.75, the ant colony number m=600, the pheromone intensity coefficient Q=0.9, the maximum iteration number Nmax=600, and the number of iterations exceeded 300, the iteration tended to be stable. The more the number of iterations of the algorithm is, the more stable the optimization result is. The optimization model can optimize the distribution cost of litchi cold chain logistics, improve the distribution efficiency of litchi and reduce the logistics cost, and provide reference for litchi cold chain logistics distribution.