The article uncovers the relevance of providing socio-pedagogical assistance and support of many-children families in the work of social pedagogue. It was found out that large families in today's unfavorable situation in Ukrainian society are in difficult life situations. There is an adverse psychological climate in the family, neglect of parental duties, negative relationships in the family and so on that prevents this family to perform their traditional functions. To activate the educational potential of large families and assistance in solving their problems is important that help and support have professional content. For this social pedagogue should be guided both by the basic principles (humanity, objectivity, consistency, tolerance, privacy, positive image of the family, equality, responsibility, human-centrism) and the specific (universality, protection of social rights, social response, preventive determination, self-reliance of the family, maximization of social resources) principles of work. For the optimization of life activity of a many-children family the social pedagogue should perform the following functions: diagnostic, security and protective, organizational and communicative, social, psychological, educational, predictive, coordination, warning and prevention, correction and rehabilitation, socio-therapeutic. These functions the social pedagogue realizes in such directions of social and educational work with large families: diagnostic, organizational, social, psychological, educational, consulting, security and protective. Based on the analysis, systematization and generalization of the research literature, social services experience, we define the content of work of the social pedagogue with large families as a system of knowledge, social skills and practical skills that allow him to effectively solve professional tasks. Its components are: knowledge of the principles of work of the social pedagogue with large families; knowledge of legal documents on social protection, social services, support and assistance to large families; knowledge of the nature, types, causes, the basic problems of large families; knowledge of technologies, forms and methods of working with large families. In this way, socio-pedagogical assistance and support of many-children families should be based on a thorough knowledge of the specifics these categories of families. Problems which characterize modern large family cause the need for its timely assistance from the state and society. Proceeding from the above, the social pedagogue who works with large families is a coordinator of the totality of social and educational support that should promote positive changes and establishing normal life of a large family by all possible means.