The structure and working principle of a new type Magnetorheological Fluid (MRF) damper is introduced. The damping force characteristic equations were established in combination with pseudo static model and Bouc-Wen model. The law of changing of MRF damper’s resistance-displacement and resistance-speed were simulated and analyzed by Matlab/Simulink software. The correctness of the mathematical model is verified, which provides a theoretical basis for the further research of MRF damper.