(Breast self-examination) BSE was reviewed in terms of effectiveness, accuracy, and acceptability. Evidence on the effectiveness of BSE is inconsistent. Some researches show the effect of BSE for early detection and better prognosis of breast cancer, but others do not. Sensitivity and specificity of BSE has not been determined yet, but they are assumed to be lower than those of the clinical examination and mammography. Education of BSE for women consistently attained an improvement in frequency and skill of BSE practice. BSE may be a useful method for detecting breast cancer at the interval of periodic clinical examination.