Abstract: Aiming at the 3-stage production-distribution system composed of producers， regional distribution centers (RDC) and distributor， the RDC lot-sizing policy was studied. First， the great common divisor (GCD) was taken as an adapted time base to optimize the production- distribution system model， and then the stationary policy was obtained. Different scenes in production-distribution process were discussed to obtain the multiple lot-sizing policies. The performance contrast standard was introduced to uncover the stationary lot-sizing model and the multiple lot-sizing model. The numerical experiments were conducted with the data from the Northeastern Chemical Sales Company of the PetroChina. The results confirm the validity of the standard and the model.

Key words: 3-stage production-distribution system, performance contrast standard, multiple lot-sizing policies;method of greater common divisor, optimal lot-sizing policy