Abstract: The object of this research is the in social rehabilitation of children with mental disability in the conditions of children psychoneurological boarding school. The actors of social rehabilitation of children with mental disability in boarding schools can become the specially training volunteers. Since 2017, the students of the department of Social Work of Altai State University implement various volunteering practices in the regional children psychoneurological establishments. One of such activities is the clown care. The subject of this research is the capabilities of volunteers-hospital clowns in social rehabilitation of children with mental disability in the conditions of children psychoneurological boarding schools. Such volunteering activities are analyzed on the basis of the theory of resiliency. The authors conducted am empirical sociological research; the main method was the questionnaire-based survey. The article gives definition to mental disability, as well as studies the statistical data on the children disability in Russia and Altai Krai. Attention is given to identification of the problems of children development in such establishments based on determination of the fundamental objectives of functioning of these institutions and the analysis of modern research on children’s’ situation in the children psychoneurological boarding schools in Russia. The authors determine the capabilities, as well as difficulties in the work of volunteers-hospital clowns, including modulation of emotions, establishment of connection, and work with special needs children.