Researchers, school personnel and parents are concerned with students' academic motivation. However, research on the topic yields ambiguous results. While adolescents in Western societies report a decline in achievement drive over the school years, adolescents in some Eastern societies may avoid this negative trend. In addition to personal characteristics, students' social relations with their teachers and peers may impact their achievement motivation. Although it is widely accepted that high-quality social relations improve motivation, research has been conducted mainly in Western societies. To address this research gap and explore students' motivational sources, this study compares students from Montréal (N = 389) and Moscow (N = 396) attending grades 7 through 9 in their socio-motivational relations and achievement motivation at school. The results of multigroup structural equation modelling suggest both differences and similarities among the student groups.