To enhance the academic achievements of Yi ethnic minority youths in rural school settings, the authors examined the effect of classmate support and the meditating role of ethnic identity in promoting their academic motivation. Cross-sectional survey data were collected from Yi youths sponsored by a philanthropic organization to attend local schools in Liangshan, rural China (n = 657; 7-12 years old; 52% boys). Results of structural equation modelling showed that classmate support positively affected ethnic identity-commitment and ethnic identity-exploration, which then had positive impacts on three academic motivation outcomes: intrinsic motivation, extrinsic motivation-external and identified regulation, and extrinsic motivation-introjected regulation. The mediating effects of ethnic identity-exploration and ethnic identity-commitment were statistically significant, except for the pathway from classmate support to extrinsic motivation-introjected regulation via ethnic identity-commitment. The authors found that ethnic identity can be facilitated through building supportive classroom environment for positive academic motivations in Yi youths. Cross-cultural significance of this study is also discussed.