BACKGROUND: Given differences in cancer survival by race, black women may differ from white women in breast cancer risk perceptions. OBJECTIVE: To evaluate black-white differences in risk perceptions of breast cancer survival and screening mammography benefit. DESIGN: A written survey was administered to a random sample of women attending general internal medicine clinics. PARTICIPANTS: Black and white women, ages 40 to 69. MEASUREMENTS: Risk perceptions were measured regarding ( 1) average 5-year survival after a breast cancer diagnosis and ( 2) relative risk reduction of screening mammography. Women's risk perceptions were defined as being accurate, as well as more or less pessimistic. Measured patient characteristics included race, age, family history of breast cancer, income, insurance, education, and numeracy. Unadjusted Pearson chi(2) tests and adjusted multivariable regression analyses were done. RESULTS: Black women were more likely than white women to accurately perceive breast cancer survival in both unadjusted (48% vs 26%, P <.001) and adjusted analyses (adjusted odds ratio (AOR) = 3.58; 95% confidence interval (CI) = 1.56 to 8.21). Black women were also more likely to accurately perceive the benefit of screening mammography in unadjusted (39% vs 15%, P < 0.001) and adjusted analyses (AOR = 2.70; 95% CI = 1.09 to 6.69). Black women were more likely to have a more pessimistic perception of mammography benefit in unadjusted (47% vs 15%, P < 0.0001) and adjusted analyses (AOR = 3.94; 95% CI = 1.62 to 9.56). CONCLUSIONS: Awareness of risk perceptions can help physicians to tailor patient education. Physician acknowledgment of more accurate risk perceptions among black women may serve as a basis to improve patient-physician communication.