Magnetorheological fluid (MRF) shows great pressure bearing capacity because of its certain viscous stress and controllable yield stress under external magnetic field.Even if overpressure happens,MRF seal can exhibit selfrepairing ability with the assistance of magnetic field when the overpressure disappears,so it has been widely used in many fields.MRF basic characteristics and its sealing applications were introduced.Relevant design issues of MRF sealing structure were discussed.In view of how to improve MRF sealing pressure drop,the main factors influencing sealing performance were expounded.The modeling approaches referring to mathematical models of MRF yield stress and MRS pressure drop were mainly illustrated based on Bingham plastic model,Biviscous model,HerschelBulkley model and HerschelBulkley model with preyield viscosity,respectively.The development trend of MRF seal was forecasted for the purpose of providing theoretical basis and technical support for research on its sealing technology and other applications.