Dependence of optimum sample rotation on sample material in Auger in-depth analysis was investigated for Al, Mo, Ag, and Ta films deposited on Si wafers, using 1 and 3 keV Ar+ and Xe+ ions as projectiles. For Ar+ and 3 keV Xe+ bombardment, depth resolution was improved by increasing the rate of rotation up to a critical rate, except for Ta. The resolution improvement resulting from sample rotation was dramatic for the samples whose surface was covered with conical projections under stationary sputtering (Al and Mo), but less dramatic or none for the samples whose surface was granulated (Ag) or fine-grained (Ta) by sputtering. Nevertheless, the critical rate of rotation was almost of the same degree, independently of the sample material and sputtering condition, except for Ta. For 1 keV Xe+ sputtering, there was no necessity for sample rotation, with regard to improving the depth resolution. Since the deviation of the rotation axis from the depth analysis point caused a discernible deterioration in the depth resolution, even if the deviation was of the order of micrometer, we concluded that stationary Xe+ sputtering at 1 keV is the best sputtering in practical depth analyses.