Breast cancer is a leading cause of death in American women. Data are lacking from representative samples of total populations on the association of risk factors for breast cancer and religiousness. The sixth cycle of the National Survey of Family Growth (NSFG VI) included 3,766 women aged 30-44 years with complete data on self-reported religiousness, and selected breast cancer risk factors. Of women in the analysis, 1,008 reported having four or more breast cancer risk factors. Women who never attended services were over seven times more likely to report having four or more risk factors than those who attended more than weekly (P < 0.0001). After adjusting for age, race, Hispanic ethnicity, nativity, education and marital status by logistic regression, women who never attended services were still over six times more likely to report having four or more risk factors (P < 0.0001). The combination of frequent attendance at religious services, very high importance of religion in daily life, and self-identification as a Protestant evangelical was particularly protective. Multiple dimensions of religiousness are independently associated with multiple breast cancer risk factors.