Objective To explore a method which is being used to screen applicable monkeys for the SIV modeling.Method The pre-infection monkey's PBMCs were cultured and infected with SIVmac251,then,the viral level was tittered and compared with the plasma viral load from the same monkey which infected with the same SIVmac251.The results were analyzed and evaluated whether it may be used to screen the applicable monkeys for SIV model.Result According to the data of 14 monkeys both in vitro and in vivo,the coincidence rate was 71.43%.There were 6 monkeys(42.9 %) with lower viral load in vivo and 4 monkeys with lower viral titer in vitro.If these 4 monkeys with lower viral titer were ruled out,there remained 10 monkeys,and there were only 3 monkeys(30%) with lower viral load among them.Conclusion By using of the method to detect PBMC viral titer in vitro,it might be helpful to choose the higher titer monkeys for modelling SIV infection efficiently.However,it isn't a perfect method.Establishing the clear genetic file of SPF monkey colony may be a reasonable way to get satisfactory monkey model for research use.