In this study,the finite element method is used to numerically simulate magnetic force acting on the magnetic particles in magnetorheological fluid under wedge-like magnetic field.The relation curves between flux and air gap width,magnetic field intensity and air gap width,flux and air gap angle,magnetic field intensity and air gap angle,has been given.The magnetic force acting on the magnetic particles in magnetorheological fluid has been calculated with virtual work method and Maxwell stress tensor method.Study results show that the flux,magnetic field intensity and magnetic force can be changed with air gap size: the flux,magnetic field intensity and magnetic force increase as the air gap width decrease.The flux,magnetic field intensity and magnetic force increase as the air gap angle increase,when the angle reached 0.61°,they began to decrease.The results provide a theoretical basis for the magnetic field design to format magnetorheological fluid suspension.