The computer fluid dynamics(CFD)software FLUENT was used to analyze the flow field of the rotorseal system with an antiswirl device.The Muszynska’s theory was used to analyze the influence of the number of antiswirl nozzle and antiswirl nozzle fluid inlet velocity on the vibration caused by fluid.The experiment was implemented to verify the numerical analysis result.The results obtained from both experimental study and numerical analysis show that antiswirl suppressing vibration caused by fluid is implemented by controlling the circumference velocity of fluid in the seal chamber.The more the number of antiswirl nozzles in the antiswirl device,the more stable is the fluid in the seal chamber,which is more helpful for suppressing the vibration caused by fluid.There is an optimal value of velocity of antiswirl,which can effectively suppress the circumference velocity,and can avoid the large vibration caused by reverse circumferential rotation of fluid.