BACKGROUND: Childhood obesity has been rising rapidly in the USA. The rate is higher among those at a lower socioeconomic status and racial/ethnic minority groups. In Alabama, nearly half of the children from rural African American families are overweight or obese. Studies suggest that children's eating behaviours and weight could be influenced by surrounding food environments. The purpose of this paper is to assess the community food environment and examine the associations with childhood obesity in Alabama's Black Belt region. METHODS: This research uses both qualitative and quantitative methods. Weight status of 613 African American students in four elementary schools in a rural county of Alabama was assessed. We examined community food environments around children's home through GIS (Geographic Information System) and statistical methods. The interrelations between children's weight and community food environments are explored with multi-level models. RESULTS: Approximately 42.1% of surveyed children were overweight or obese, much higher than the national average, 30.6%. In Model 1, convenience stores (3.44; P < 0.01), full service restaurants (8.99; P < 0.01) and supermarkets (-37.69; P < 0.01) were significantly associated with the percentile of body mass index. Fast food stores (-0.93; P = 0.88) were not related to children's weight. In Model 2, the additions of sociodemographic factors and school effects cause significant changes of the relationships between children's weight and four types of food outlets. The percentage of African American population (90.23, P < 0.01) and school (6.68, P < 0.01) were positively associated with children's weight; while median household income (-39.6; P < 0.01) was negatively related to it. CONCLUSION: Children's weight is influenced by community food environments, sociodemographic factors and school context. Findings suggest that policymakers and planners need to improve community food environments of low-income minority communities. Parents and schools should pay more attention to reduce the negative impacts of food environments on children.