In order to study the resistance characteristics of orificeseparator,which is widely used in aeroengine lubrication and ventilation system,taking general structure of the orificeseparator as model,the typical characteristics were illustrated,and the orifice feature and release cavity were identified.According to the theory,the resistance mechanism of orifice structure was analyzed,the rotatecorrecting coefficient was obtained and the resistance algorithm of the orificeseparator with blades was established.The accuracy of the resistance algorithm was verified by CFD simulation and component experiment results,and the applicability of the algorithm in the simulation calculation of lubrication and ventilation system was verified by the oilvent system test.The influences of relevant factors,defined as revolving radius,orifice area,flow rate and rotating speed on the resistance characteristics of orificeseparator were analyzed based on the resistance algorithm of orificeseparator.The conclusion was drawn that the resistance was positive correlation with revolving radius and flow rate,but negative correlation with orifice area.