Аннотация:The present article analyzes the influence of social environment factors on the emergence, dynamics of development and treatment of anorexia nervosa in the adolescent girls. It presents the data of some studies about the socio-cultural conditionality of the disease as well as studies of some small social groups, which confirm the significance of micro- and macro-social impact on the growth of risks of anorexia manifestation. We describe the influence of bullying in school and in social networks communities on the dynamics of symptoms in anorexia nervosa. The results of the analysis of psychotherapy with 13 girls with anorexia nervosa and families are presented. We have identified the features of their interaction with the family, group of peers and social networks in the Internet. We analyze the influence of relationships within those social groups on the symptoms dynamics in anorexia nervosa, propose the targets of psychotherapy, and substantiate the need to work not only on the individual but also on the systemic level in the provision of assistance. The opportunities of positive dynamics in the treatment of anorexia nervosa in adolescents by means of changes in the social environment around girls require further investigations and accumulation of the data obtained during the psychological assistance.