Abstract: Due to problems of low magnetic field utilization of Magneto-rheological（MR） fluid shock absorber,a MR fluid shock absorber based on multi-radial flow mode is put forward.As the controlled media,rheologic characteristics and magnetization performance of MR fluid are studied.The magnetization performance parameters of the selected magnetic materials have been identified by the least square regression method.Based on the magnetic theory,the equivalent magnetic circuit model is derived,along with the expression of the relationship between the magnetic induction of the working gap and the exciting current of the field coil.In order to verify rationality of theory,the simulation is given by finite element method for the magnetic path in the MR valve.A kind of MR fluid shock absorber based on multi-radial flow mode is designed and fabricated according to technical requirements of railway vehicle anti-yaw shock absorber.The magnetic induction at the working gap which compared with theoretical values are tested by the Hall sensor of A1322ELHLT-T3.