Functional somatic symptoms (FSS), defined as physical symptoms that cannot be fully explained by organic pathology, are prevalent in youngsters worldwide. When severe, they can pose a major burden on the affected individual as well as on society. FSS seem to aggregate in families, and family variables may play a key role in symptom development and perpetuation. It may, therefore, be important to work with the family when managing FSS. The aim of this systematic review was to explore and describe family-based interventions used for children and adolescents with FSS, further to evaluate the overall quality of the research in this area. Sixteen studies were included. The psychological orientation for the applied treatment was based on systemic or cognitive behavioural therapy. Treatment focused on family illness beliefs and on a shift away from somatic symptom attribution to alternative explanations that were shaped by the psychological orientation of the applied treatment. Practitioner points: Family influences are significant for functional somatic symptoms in youngsters Family intervention may be a relevant treatment approach for youngsters with functional somatic symptoms Family-based psychotherapy for youngsters with functional somatic symptoms is mainly based on cognitive behavioural therapy or on systemic family therapy Illness beliefs of the child/adolescent as well as illness beliefs of the family as a whole could be important treatment targets in young people with functional somatic symptoms.