A survey on factors related to breast cancer screening was completed by 179 U.S.-resident women of Mexican descent who were either Mexican born (n = 76) or U.S. born (n = 103). The U.S.-born women had significantly higher levels of income, education. and acculturation and were significantly more likely to be covered by health insurance and to receive health professional interventions such as breast self-exam (BSE) instruction. Accordingly, these U.S.-born women engaged in BSE more frequently and were more motivated to engage in other health behaviors. In comparison, the Mexican-born women reported significantly greater beliefs that breast cancer is a serious illness and that they were relatively more susceptible to this illness. For the Mexican-born women health locus of control was significantly more geared toward powerful others and chance factors. Factor differences suggest that Mexican-born women face more breast cancer screening barriers than the U.S.-born women of Mexican descent.