A self-administered questionnaire was given to 6380 female secondary-school students (mean age = 18.1 years) in Jeddah to identify their knowledge of breast cancer and attitude towards breast self-examination (BSE). Knowledge of risk factors and presentation was very low. Over 80% of students failed to answer 50% of the questions correctly. A higher knowledge level was associated with older age, marriage and having children. Also students who had undergone mammography, had been exposed to breast surgery or had a positive family history of breast cancer showed significantly higher knowledge levels. Only 39.6% reported ever hearing of BSE and only 14.4% and 7.1% respectively knew the correct frequency and timing. However, 82.4% had a positive attitude towards learning BSE.