Abstract: In the actual working process of magnetorheological polishing, the difference of the geometric characteristics of the polished area will have a great influence on the key parameters of the flow field creation. However, there is still a lack of research in this area, so this article establishes a three-dimensional model and experimental simulation for this problem. In studying the relationship between the geometric characteristics of the polished area and the key parameters of the flow field creation, first change the shape of the polished area to observe its influence on the shear stress and pressure in the flow field creation; when the shape of the polished area is the same, change the size of the polished area and observe its effect on the shear stress and pressure in the creation of the flow field. It is found that when the shape of the polished area differs, the shear stress is the largest when the polishing area is concave, while it is the smallest when the polished area is convex. When the polished area is convex, the shear stress on both sides of the polished area increases as the curvature of the polished area increases; when the polished area is concave, the shear stress on both sides of the polished area increases as the curvature of the polished area increases. When the shape of the polished area is different, the pressure is maximum when the polished area is concave, and the pressure is minimum when the polished area is convex. When the shape of the polished area is convex, the pressure at the polished area increases as the curvature of the polished area increases; when the shape of the polished area is concave, the pressure at the polished area decreases as the curvature of the polished area increases.