Atomized aluminium powder is ground in the presence of stearic acid in a laboratory vibration mill at different conditions in order to study the effect of feed size, additive concentration, weight ratio of the feed to grinding media and ball filling on the grinding characteristics. Feed size is found to be an insignificant variable in the range studied. While a stearic acid concentration of about 3% is desirable, higher concentrations result in a reduction in the rate of grinding. A lower weight ratio assures a higher rate of grinding whereas higher ball filling is preferable considering the increased production of fines. © 1992, Society of Powder Technology Japan. All rights reserved.