Correlations between indices of family burden and changes in children's social functioning during psychosocial group therapy with parents of children and adolescents with schizophrenia spectrum disorders have been studied. A sample included 140 children and their mothers. Family burden was considered as a separate "target" of psychosocial rehabilitation of children and adolescents with mental disorders. The authors recommend to use this dynamic characteristic of family burden in the development of individualized treatment/prevention programs (modules) and corresponding measures with assessment of their effectiveness in the implementation of psychosocial support to the family. A significant positive effect of this psychosocial group therapy was confirmed by a set of specific scales and questionnaires.