To study the flow regime of magnetorheological(MR) fluid in porous metal foam,the control equation that MR fluid flows in the porous metal foam was established based on theory of magnetohydrodynamics and Maxwell.By using software of Fluent,the flow state of MR fluid in porous metal foam was simulated,and the distribution of pressure and velocity was obtained.The results show that the larger the magnetic field,the more obvious the laminar flow,however,the velocity perpendicular to the fluid is decreased gradually due to the complexity of foam metal.The MR fluid is still able to flow out from the metal foam even by applying the magnetic field perpendicular to the direction of flowing.The dynamic pressure is decreased,while the static pressure is increased gradually as increasing the magnetic field.