Background: Energy balance-related behaviors (EBRBs) are behaviors closely related to energy intake and expenditure. Unhealthy EBRBs are closely related to overweight and obesity in primary school students, and personal and family factors are the key factors that affect the EBRBs of primary school students.Methods: In order to explore the relationship between EBRBs, related factors, and overweight and obesity among school-age children, the body mass index of 4,412 10–12-year-olds from North China, Northeast China, Northwest China, and Southwest China was measured, and they were assessed using a questionnaire regarding EBRBs and influencing factors.Results:1.Compared with normal-weight students, the number of breakfasts consumed per week by overweight/obese students was significantly higher (p <0.01), and the weekly screen-viewing time was significantly longer (p <0.01).2. There are some differences in influencing factors of EBRBs between overweight/obese pupils and normal weight pupils. Overweight/obese students' health beliefs, parental subjective norms, parental modelling, parental practices, and home availability scores increased significantly in terms of beverage consumption behavior (p <0.01 or p <0.05).The scores of attitude, health beliefs, self-efficacy, parental subjective norms and active encouragement decreased significantly in terms of breakfast consumption (p <0.01 or p <0.05).The health beliefs scores of physical activity increased significantly (p <0.01), and preference and autonomy scores decreased significantly (p <0.01). The health beliefs, parental subjective norms and parental practices scores of screen-viewing activities increased significantly (p <0.01 or p <0.05). 3.Breakfast consumption (odds ratio [OR]: 0.911; 95% confidence interval [CI]: 0.870–0.954) and screen-viewing activities (OR:1.055; 95% CI: 1.030–1.080) were negatively correlated and positively correlated with overweight/obesity, respectively.4.Factors that significantly influenced weekly breakfast consumption included attitude, health beliefs, self-efficacy, parental subjective norms, and active encouragement. The main factors that influenced weekly screen-viewing time were parental practices, self-efficacy, preference, attitude, autonomy, and parental modelling.Conclusions: Irregular breakfast consumption and excessive screen-viewing time engagement are key EBRBs associated with overweight/obesity among Chinese primary school students aged 10–12 years. Unhealthy breakfast consumption and screen-viewing activities of overweight/obese students are associated with an interaction between individual and family factors.