Optimization of regional DC is a study on deciding the location and inventory strategy to get a minimal Total Relevant Logistic Cost-TRLC, with a certain service level. This paper studies the modeling and optimizing methods of logistic systems with determinate lead time,batch discount, (T, s, S) inventory strategy, stochastic demand. Firstly, this paper builds DC's TRLC model, and then by the WITNESS simulation and optimization software package, studies the location of regional DC, Finally, gives sensitivity analysis betweens, S, LT and transshipment times, order times, and shortage times, obtains the relevant relation table between variables and performance indexes.