Background: Childhood obesity has become an important public health problem in Thailand. This study aimed to determine the relationship between self discipline and obesity in Bangkok school children. Methods: A case control study was conducted. 140 cases (obese children) and 140 controls (normal weight children) were randomly chosen from grades 4-6 students in 4 Bangkok public schools. Questionnaire responses regarding general characteristics and child self-discipline were obtained from children and their parents. Results: Self discipline in eating habits, money management and time management were reported at significantly lower levels among the obese group (p < 0.05). After controlling all other variables, it was revealed that the ranking of factors associated with obesity by adjusted odds ratio (OR) were low self-discipline in managing expenses (3.1), poor home environment (3.0,), moderate self-discipline in time management (2.9), television viewing time =2 hours/day (2.6), an obese father (2.2), and an obese mother (1.9). Conclusions: It was recommended that parents and teachers participate in child self-discipline guidance, particularly with regard to eating habits, money management and time management in a supportive environment that both facilitates prevention of obesity and simultaneously develops a child's personal control. [ABSTRACT FROM AUTHOR]