Objective: To explore the associations of family structure with adolescent mental health and health associated behaviors, to support interventions to decrease the occurrence of psychological problems and adverse health associated behaviors among adolescents in families without two parents. Methods: The multi stage stratified random cluster sampling method was used to select 18 700 adolescents of the 13 districts and cities from Jiangsu Province for a questionnaire survey on mental health and health associated behaviors, to compare differences in mental health and health associated behaviors among adolescents with different family structures. Results: Among the adolescents, 82.1% had two parent families, 8.6% had single mother families, 4.0% had single father families, and 5.3 % had families with both parents absent. After controlling for age, urban/rural areas, gender, academic period and region, Logistic multivariate regression analysis showed that compared with adolescents from two parent families, the incidence of depression, social anxiety and bullying on campus of adolescents with single mother families increased significantly( OR=1.31, 1.15, 1.36，P ＜0.05). Compared with adolescents in two parent families, adolescents in families without two parents had significantly more types of health risk behaviors, and those in single mother families had significantly less frequent intake of a healthful diet( OR =0.81), significantly more smoking( OR =1.20), drinking behaviors( OR =1.22), and significantly less moderate intensity physical activity ( OR =0.84) and shorter duration of sleep( OR =0.87)( P <0.05). Conclusion Psychological and health associated problems were significantly higher among adolescents in families without two parents than in those with two parent families. Psychological problems and adverse health associated behaviors were particularly prominent among adolescents in single mother families.