In the present study, an experimental study on surface roughness (SR) of granitic rocks sawn by diamond disc cutters was presented. Effect of each operating variable on the SR was determined. Morphologies of wearing surfaces of rocks were evaluated using scanning electron microscope (SEM) images. Results showed that the SR increased with respect to the increase in peripheral speed, traverse speed, and cutting depth and decreased with the increasing of flow rate of cooling fluid. Peripheral speed and traverse speed were determined as the most significant operating variables affecting the SR.