To manage and control grinding process theoretically, the cutting-edge density should be quantified. In this study, the estimation method of the grain-height distribution, which is necessary to quantify the cutting-edge density, has been examined. From the results of simulation by modeling the grain distribution of a grinding wheel, the close correlation has been confirmed between the grain-height distribution and the peak-height distribution of the working surface profile. Based on this, the grain-height distribution can be estimated from the peak-height distribution by narrowing the width accompanied maintaining the total frequency. Since the estimated grain-height distribution agreed well to the distribution determined from the measured 3D-topography, the validity of the method has been confirmed.