Magnetorheological (MR) jet polishing (MJP), a new type of precision polishing technology in the material removal mechanism, was studied by the method of computational fluid dynamics (CFD). In MJP, the MR jet containing abrasives was magnetized by a local longitudinal magnetic field near the exit of the nozzle so that it could maintain the coherent and stable structure for a long distance. Firstly the mechanism and experiment set-up of MJP were introduced. Secondly the formation of collimated MR jet in a uniform axial magnetic field was analyzed. And then a series of static experiments were conducted to show the characteristics of the distribution of the material removal during the process of MJP. Finally the characteristics of the power density under conditions of both normal and oblique impingements were simulated by CFD method. Simulation and experiment results demonstrate that the material is removed by shearing actions caused by the radial spread flow of the MR jet over the workpiece surface. The method of CFD can accurately predict the 3-D removal rate distribution (polishing spot), thereby facilitating the accurate prediction of spot shapes on surface geometries.