Abstract The effectiveness of outdoor activities in promoting health in children and adolescents has been validated. However, outdoor activity time among children and adolescents has gradually decreased, posing a significant challenge to children s physical and mental health. Current research suggests that behavioral interventions can effectively increase outdoor activity time among children and adolescents. The study reviews the decline in outdoor activity time, insufficient outdoor activity time, and low compliance, and expounds on the research progress of increasing outdoor activity time through multi level behavioral interventions at the individual, interpersonal, and school levels. It provides a scientific basis for the formulation and implementation of relevant policies and measures for outdoor activities.