Surface roughness is one of the most important parameters in grinding, which directly affects the quality of the processed surface and has quite a lot of effect on the shape and position accuracy, installation accuracy of the workpiece. In the grinding process, the surface roughness is formatted from the abrasive which effects on the surface of spherical head, and is the result of mutual interference between abrasive and spherical head. Many factors affect the surface roughness, such as the shape and size of contact roller, abrasive morphology, grinding method, the stiffness of machine tool and workpiece, abrasive wear and vibration in the machining process. All of these have an impact grinding surface roughness. In this paper, analyzed the belt speed, workpiece speed, abrasive size, workpiece diameter, sand-planting density on the surface roughness of spherical head in experimental. And the effect trend of factors on surface roughness of workpiece was analyzed. Some valuable information was provided for selecting suitable parameter in spherical head grinding.