Although the relationship between socioeconomic status (SES) and health is well-established in Western industrialized countries, few studies have examined this association in developing countries, particularly among older cohorts. We use the Mexican Health and Aging Study (MHAS), a nationally representative survey of Mexicans age 50 and older, to investigate the linkages between three indicators of SES (education, income, and wealth) and a set of health outcomes and behaviors in more and less urban areas of Mexico. We consider three measures of current health (self-rated health and two measures of physical functioning) and three behavioral indicators (obesity, smoking, and alcohol consumption). In urban areas, we find patterns similar to those in industrialized countries: higher SES individuals are more likely to report better health than their lower SES counterparts, regardless of the SES measure considered. In contrast, we find few significant SES-health associations in less urban areas. The results for health behaviors are generally similar between the two areas of residence. One exception is the education-obesity relationship. Our results suggest that education is a protective factor for obesity in urban areas and a risk factor in less urban areas. Contrary to patterns in the industrialized world, income is associated with higher rates of obesity, smoking, and excessive alcohol consumption. We also evaluate age and sex differences in the SES-health relationship among older Mexicans. The results suggest that further economic development in Mexico may lead to a widening of socioeconomic inequalities in health. The study also provides insight into why socioeconomic gradients in health are weak among Mexican-Americans and underscores the importance of understanding health inequalities in Latin America for research on Hispanic health patterns in the US.