Black women are at increased risk for breast cancer mortality. The black category is assumed to be homogeneous, an assumption that may be misleading. This study aims to examine the relationship between nativity and breast cancer risk factors among women identified as black. A sample of 236 black women over 18 years of age in Brooklyn, New York, was recruited. Data were collected on race/ethnicity, breast cancer risk factors, and other sociodemographic, behavioral, and early life experience factors. Logistic regression analyses were used to estimate prevalence ratios for association between nativity and breast cancer risk factors. US-born blacks were more likely to be unemployed, smoke, not breastfeed, and breastfeed for a shorter duration than foreign-born blacks (all p< or =0.01). Foreign-born blacks were more likely to have parents who achieved at least a high school education (p<0.05). After adjustment for smoking, employment, and parental education, US-born blacks were twice as likely to never breastfeed (PR 2.2, 95% CI: 1.1, 4.46) compared to foreign-born blacks. Among women who breastfed, US-born blacks were also less likely to breastfeed for 6-11 months or more than 12 months, but these associations were not statistically significant. Because lactation reduces breast cancer risk and is a leading modifiable risk factor, understanding its variation within black women will help physicians and public health practitioners to target patient counseling and education of breast cancer risk.