This paper addresses the use planning of public distribution centers in a dynamic distribution system that consists of distribution centers and retailers. Public distribution centers are used as the distribution centers in a distribution system. In discrete and finite time periods, the demand of retailers is changed dynamically for the time periods. The use planing is to determine the locations, the time periods and the number of storage bin of public distribution centers to be used for the given time periods to minimize the total cost. Cost factors are fixed cost and variable cost for use of distribution centers, and transportation cost from the distribution centers to the retailers. A mathematical model is formulated and a genetic algorithm is developed. Numerical examples are shown.