Background: This study examined the moderating role of social support in the acculturation-obesity/central obesity relationship in Mexican American (MA) men and women. Methods: Data from NHANES 1999-2008 were used. Acculturation derived from language use, country of birth and length of residence in the U.S. Social support assessed emotional and financial support. BMI (≥30) and waist circumference (≥88 cm for women; ≥102 cm for men) measured obesity and central obesity, respectively. Weighted multivariate logistic regression models were used to describe associations. Results: Compared to less acculturation, more acculturation was associated with higher odds of obesity (ORs 2.48; 95% CI 1.06-5.83) and central obesity (2.90; 1.39-6.08) among MA men with low/no social support, but not among MA men reporting high social support. The modifying effects was not observed among women. Conclusion: Higher amounts of social support appeared to attenuate the risk of obesity/central obesity associated with acculturation. Interventions enhancing social support maybe effective among acculturated MAs, particularly among men.