The article presents a study of the image of a social group a certain level in the circle of family and kinship – nagasanar (next to the family of blood relatives on the maternal side), including the problems of terminology, characteristics, values and forms of social ties that bind this group with others. Relatives were mandatory participants of all the important events in the group. Its position as the main relative, Uncle nagatsa, and in general, the relatives on the maternal side nagasanar stored in modern Buryat families. Relationships with relatives on his mother's side in most of the Buryat families considered as paramount and there is a belief that kinship through the mother has traditionally been closer. Modern Buryat families, especially urban circle of close contacts are largely limited cousins. And Buryat family is characterized by close ties with relatives nagasanar group.