Abstract: This paper describes application of GPSS simulation technique to farms With swine Re-production system and it was simulated five years with the background of Yong Ledian state Farms, Chai Changtun Branch, Brijing. The established GPSS model will be able to simulate state of system on conditionof breed originated from one single individual with purchace piglet at vary scale and will provide base of quantitatively analysis for decision of swine Re-production.