Objective: Obesity is a complex disease that involves interactions between environmental and genetic factors in its pathogenesis. The aims of this present study were to analyse the overall effects of some nutritional, physical and genetic factors with childhood obesity, and to build predictive models of childhood obesity.Material and Methods: A case-control study was conducted on 559 Hanoi primary school children (278 obese cases and 281 normal controls). Genetic analysis was performed to evaluate genotype on the rs6265 gene BDNF, rs6548238 gene TMEM18, rs6499640 gene FTO, and rs17782313 gene MC4R. Univariate and multivariate regression analysis were conducted to compare the two groups of children, so as to draw conclusions regarding influencing factors and to establish predictive models of obesity for Hanoi primary school children.Results: Factors increasing the risk of obesity found included: urban living areas (odds ratio (OR)=1.5), caesarean section (OR=2.1), high birth weight (OR=1.9-3.1), parental overweight and obesity (OR=2.1-5.1), short night sleeping times (OR=2.6), characteristics of child feeding; including early weaning (OR=2.1), gluttony (OR=19.1), no snacking (OR=2.4), controlled eating (OR=2.4) fat food hobbies (OR=2.7), and CC rs6548238-TMEM18 genotype (OR=1.8). A predictive model of childhood obesity for Hanoi primary school children was built, based on the BMI of parents, gluttonous characteristics, unrestricted eating with ROC=0.871.Conclusion: Childhood obesity develops as a result of interaction between eating habits, lifestyle characteristics of the child and genetic characteristics inherited from over nutritious parents. Encouraging parents to manage both their own weight and their children’s eating habits such as allowing children to consume food without undue restriction and reducing gluttony can serve as effective interventions to diminish the prevalence of childhood obesity within the community.