Objective: To analyze the correlation and gender differences between adverse childhood experiences (ACEs) and positive childhood experiences (PCEs) and depression and anxiety symptoms among middle school students, so as to provide a reference for promoting the mental health of middle school students. Methods: With a stratified random cluster sampling method, a total of 6 656 middle school students in 4 cities, including Nanchang, Shenyang, Taiyuan, and Zhengzhou, were selected as research subjects from October 2021 to October 2022. The Adverse Childhood Experiences International Questionnaire (ACEs-IQ), Benevolent Childhood Experiences Scale (BCEs), Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorders-7 (GAD-7) scale were used to conduct questionnaire surveys.The Chi square test was used to compare the reporting rates of depression and anxiety symptoms among middle school students in different groups, and a Logistic regression model was established to analyze the effects of ACEs and PCEs on depression and anxiety symptoms among middle school students and their gender differences. Results: The reporting rate of depressive symptoms among middle school students was 20.1%, and the reporting rate of anxiety symptoms was 13.9% . ACEs were positively correlated with depression and anxiety symptoms among middle school students (depression symptoms: OR =1.20, 95% CI =1.18-1.22, anxiety symptoms: OR =1.18, 95% CI =1.16-1.20), while PCEs were negatively correlated with depression and anxiety symptoms among middle school students(depression symptoms: OR =0.84, 95% CI = 0.83 -0.86, anxiety symptoms: OR =0.85, 95% CI =0.83-0.87) ( P <0.05). In the general population (depression symptoms ： OR =0.99, 95% CI = 0.98- 0.99, anxiety symptoms: OR =0.99, 95% CI =0.99-1.00) and among girls (depression symptoms: OR = 0.98 , 95% CI = 0.97- 0.99 , anxiety symptoms ： OR =0.99, 95% CI =0.98-1.00), the interaction term between ACEs and PCEs were negatively correlated with depression and anxiety symptoms ( P <0.05). Conclusions ACEs significantly affect the depression and anxiety symptoms of middle school students, while PCEs can help reduce the impact of ACEs on the depression and anxiety symptoms of middle school students, girls are more susceptible to the impact of early experiences than boys. It should focus on gender differences, formulate comprehensive mental health protection strategies, to promote the mental health development of middle school students.