Introduction. Obesity is a pandemic in Mexico. The purpose of this study was to assess the environmental factors that have the strongest association with obesity and abdominal obesity among adults in Tijuana. Methods. Four neighborhoods differing in socioeconomic status were chosen. A questionnaire for weekly walking, social cohesion, satisfaction with their community, weekly income, and convenience store, education, family income, crime safety, pedestrian safety, street connectivity, walking/cycling facilities, and sociodemographic characteristics was administered. Weight, height, and waist circumference were measured. Univariate and multivariate binomial logistic regressions were conducted. Results. Three hundred and twenty-two (322) individuals, 70% females with a mean age of 39 years, were assessed. The prevalence of obesity and abdominal obesity was 27% and 43.5% respectively. The odds ratio for obesity and abdominal obesity among those living in the lowest-income neighborhood was 2.4 and 7.8 respectively, compared with those living in a middle-class neighborhood. Conclusions. Residence in a low-income neighborhood was a predictor for obesity.