A review of publications to the criteria and quantitative assessment of shape-similarity projection of the abrasive powders grains has been carried out. It has been established that the existing set of shape-similarity indexes is not enough for the most adequate comparative evaluation of the of such powders quality. It was proposed to supplement this set of shape-similarity indexes with a new generalized form-like index, called the uniformity coefficient of abrasive powders according to the shape-similarity of the projection of their grains. An analytical relationship to determine the numerical values of the entered uniformity coefficient was obtained. The results of testing of the developed methodological tools on various abrasive powders are given. Testing is illustrated by photographs grains of these powders, which allows to realizate the objectivity of the comparative evaluation of powders according to the coefficient of uniformity. (C) 2019 Elsevier B.V. All rights reserved.