Abstract: Based on a field survey, this paper compares the current situations of adolescents' heritage language maintenance in Salar,
Ewenki, Daur and Xibo groups from the perspectives of whether, when and how adolescents have acquired their mother tongues, their
levels of mother tongues, the ways to maintain mother tongues, the status quo of and their confidence in mother tongues maintenance.
At last, types of mother tongue maintenance in ethnic groups with less population are drawn based on the results.

Key words: ethnic groups with less population, adolescents, heritage language maintenance