Objective: To explore the relative effects of various forms of childhood maltreatment on adolescent anxiety and depression and to explore possible sex difference. Methods: By using convenient sampling method, 6 228 middle school students were selected from 2 middle schools in Chongqing. Self reported questionnaires were used to collect demographic characteristics, childhood maltreatment experiences, anxiety and depression symptoms. The relative weights analysis was conducted to analyze the relationship between childhood maltreatment forms and adolescent anxiety and depression and possible sex differences. Results: The prevalence of physical neglect, emotional abuse, physical abuse, emotional neglect and sexual abuse was 28.2%, 23.7%, 16.0 %, 12.4% and 10.3%, respectively. Among them, emotional abuse had the greatest impact on anxiety and depression ( R 2= 0.12 /0.15), followed by emotional neglect( R 2=0.08/0.11), physical abuse ( R 2=0.02/0.03), sexual abuse ( R 2=0.02/0.01) and physical neglect ( R 2=0.01/0.01). Compared with boys ( R 2=0.09/0.12, R 2=0.06/0.09), emotional abuse ( R 2=0.13/0.16) and emotional neglect ( R 2=0.10/0.13) had greater impacts on anxiety and depression among girls. Conclusion Psychological maltreatment (including emotional abuse and emotional neglect) in childhood has the greatest influence on anxiety and depression, especially for girls.