The article focuses on the current problem of the influence of grade-rating system upon academic motivation of students. The analysis of grade-rating system and its aims and functions is revealed. Special attention is paid to one of the main functions: the motivational-stimulative function. The results of empirical study of the influence of grade-rating system upon academic motivation of students are also analyzed. The data on students’ satisfaction/frustration of this system are represented. The article reveals the fact that the students satisfied with GRS have prevailing extrinsic educational motives whereas the students dissatisfied with GRS have prevailing intrinsic educational motives. The motivational-stimulative function of GRS is realized in providing one type of students with additional motivation and giving the other type of students the opportunity to focus efforts on learning activity and teaching them methodic work that helps to develop intrinsic motives.