Objective: To investigate the association of physical activity and screen time with overweight and obesity among children and adolescents with special needs in Tianjin, so as to provide scientific evidence for childhood obesity prevention and intervention measures in the population. Methods: From January 2022 to June 2024, 296 children and adolescents with intellectual disabilities and autism spectrum disorders aged 2-18 years were recruited from special education schools and institutions in Tianjin. Height and weight were measured, and a standardized questionnaire was used to assess physical activity and screen time. Binary Logistic regression analysis was carried out to investigate the association of physical activity and screen time with overweight and obesity. Results: The prevalence of overweight and obesity among children and adolescents with special needs in Tianjin were 17.2% and 21.6%, respectively, and the combined prevalence of overweight and obesity was 38.9%. The median of moderatetovigorous physical activity (MVPA) time was 0.20 h/d, and physical activity sufficiency rate was 7.8%. The median of screen time was 1.79 h/d, and the screen time compliance rate was 68.2%. The binary Logistic regression results showed that lower levels of MVPA time and increased screen time were associated with a higher risk of overweight and obesity among children and adolescents with special needs [OR(95%CI)=1.80(1.06-3.07), 2.40(1.42-4.07),P<0.05]. Conclusions Insufficient physical activity and excessive screen time are associated with an increased risk of overweight and obesity among children and adolescents with special needs. Therefore, comprehensive intervention measures should be implemented as early as possible to prevent and reduce the incidence of overweight and obesity in this population.