Health risk behaviour contributes markedly to today's major killers. A descriptive cross-sectional study was conducted to assess current awareness and practice of health risk behaviour among Egyptian university students. Only 121 students (18%) were practising risky behaviour. Tobacco use, alcohol and drugs use and risky sexual behaviour were positively correlated. Multiple regression analysis revealed that the main determinants of risky behaviour were being a male, of older age, having a high allowance and having no attention to danger. About 30% of students lacked adequate knowledge on AIDS. Most of those who had sexual relationships did not use contraceptives or any method of protection from sexually transmitted infection. Main sources of knowledge were the media (38%) then peers (30%).