Breast cancer is significant among women that the last time. The purpose of this study is determination of the knowledge of mar - ried women between 15-49 ages about Breast Self-Examination for early detection of breast cancer. This study conducted on a group of women 321 who live in Ergene District. As the results of this study, half percentage of women % 44.2 found to have a knowledge about breast self-examination but % 6.2 women only answered the questions accurately.