BACKGROUND: Breast cancer is the leading cause of cancer mortality worldwide; therefore rnhas become a global health problem. According to the American Cancer Society; about 1.3 rnmillion women will be diagnosed with breast cancer annually worldwide and about 465,000 will rndie from the disease. Breast cancer was considered as a disease of the developed countries but rnnow a day the incidence of breast cancer in the developing countries is rising. In Ethiopia breast rncancer is the second most often occurring cancer (cervical cancer is first) among women. Early rndiagnosis is especially important for breast cancer because the disease responds best to treatment rnbefore it has spread. To do this knowing the screening techniques like breast self examination, rnclinical breast examination and mammography is legitimate. It is therefore important for nurses rnas educators to have appropriate information and positive attitude toward breast cancer early rndetection (screening techniques) of breast cancer. Nursesâ€™ knowledge and awareness of breast rncancer screening behavior for themselves and would also impact patientsâ€™ behavior by increasing rntheir awareness. rnOBJECTIVE: Assessment of Knowledge of Breast Cancer and Screening methods among rnNurses in University Hospitals in Addis Ababa, Ethiopia. rnMETHOD: Descriptive cross-sectional design was used with simple random sampling technique, rnon sample of 281 nurses at university hospitals of Addis Ababa. Data collection took place on rnMarch, 2011 using self administered questionnaire to obtain information such as demographic rncharacteristics, knowledge of breast cancer and screening method. To see the association rnbetween the independent and the dependent variable bivariate analysis was made and crude OR rncorrespondence to 95% C.I was calculated. Multivariate analysis was manipulated to see the independent variable effect on the dependent variable and adjusted OR on 95 % C.I and rnstatistical significance at p