In order to develop the transshipment and processing capacity of port nodes in the container port service network and meet the increasing demand for cold chain logistics transportation, container flow quantity should be reasonably distributed in port nodes which undertake functions of transportation and transfer in the cold chain. Through the study of refrigerated container service network, this paper establishes an optimization model for port service network of refrigerated container with minimizing the total cost as the objective, transportation time reliability and storage capacity of the refrigerated container in port nodes as constraints to achieve the optimal container flow allocation in transshipment ports under different supply and demand quantity.