Abrasive jet finishing process is a novel process whose objective is to remove surface defect layer and to diminish roughness and ripple after grinding. Experiments were performed with plane grinderM7120 and workpiece material 45# steel which was ground with the surface roughness values of Ra =0.2-0.6 μm . The machined surface morphology was studied using SEM and the microcosmic geometry parameters were measured with MICROMESVRE2 instrument. In this paper, with the fractal dimension, Ra , Rq and the supporting rate curve, the surfaces of grinding machining and abrasive jet finishing machining were researched. The result indicated that the machined surfaces changed from continuous parallel micro-groove and plough to randomly distributed discontinuous micro-pit could be observed with the increase of machining circles and surface roughness was obviously improved. Furthermore, the isotropy surface and uniformity veins both parallel and perpendicular machining direction were attained by abrasive jet precision finishing with grinding wheel as restraint. The supporting rate curve of the surface profile can be increased. This is favorable for the wearable capability of the workpiece.