In recent years， mental disorders among children and adolescents in China have shown a trend toward occurring at young ages and becoming severe， placing a heavy burden on families and society. While traditional rehabilitation models have shown some effectiveness in alleviating symptoms， the persistence or recurrence of the condition remains a pressing challenge in this field. The theory of emotional contagion explains how emotions are transmitted and influence from person to person. Research has shown that these factors are closely related to children's and adolescents' cognition， emotions， and behavior， but have not received sufficient attention in the clinical rehabilitation of mental disorders in this population. This paper systematically reviews the theoretical framework of emotional contagion and its impact on children and adolescents， and explores in depth how to optimize rehabilitation strategies for children and adolescents with mental disorders from the perspective of emotional contagion. Rehabilitation effectiveness can be improved by establishing a positive emotional support system and therapeutic environment， aiming to provide guidance for clinical practice in children and adolescents with mental disorders.