BackgroundIn most resource constrained settings like Nigeria, breast self-examination self-breast examination (BSE) is culturally acceptable, religious friendly and attracts no cost. Women's knowledge and beliefs about breast cancer and its management may contribute significantly to medical help-seeking behaviours. This study aimed to assess knowledge and beliefs of BSE among market women.MethodsA descriptive cross-sectional study was conducted among 603 market women in Ibadan, Nigeria. Data was collected using semi-structured interviews and analyzed using descriptive and analytic statistical methods.ResultsThe mean age of the respondents was 34.6±9.3 years with 40% of the women aged between 30-39years. The proportion of married women was 339 (68.5%) with 425 (70.8%) respondents reporting that they do not know how to perform BSE. However, 372 (61.7%) women strongly agreed that BSE is a method of screening for breast cancer. Highest proportion 219 (36.3%) reported that the best time for a woman to perform BSE was ‘anytime’. Most of the respondents believed breast cancer is a dangerous disease that kills fast and requires a lot of money for treatment.ConclusionMore efforts are needed in creating awareness and advocacy campaigns in the grassroots in order to detect early breast cancer and enhance prevention strategies that would reduce the burden of breast cancer in Nigeria.