Sexually transmitted diseases (STDs) remain an important cause of morbidity and mortality among women in the child-bearing age. In order to institute appropriate preventive measures there is need to establish the profile of knowledge of the predisposing factors and causation of STDs, attitude to sexual practice and sexual patterns among the susceptible young people, such as university students. Non medical university students, Makerere University. Descriptive cross sectional study. A detailed questionnaire identifying socio-demographic characteristics, sexual patterns, knowledge of STDs as well as attitudes towards prevention of STDs was administered to 400 non medical university students of Makerere University. Knowledge of the clinical features of gonorrhoea and AIDS was high; most knew the predisposing factors for STDs (multiple sexual partners 90%; unprotected sexual intercourse 93%; rape 81%; sex outside marriage 78%, and sex under the influence of alcohol 73%) but not so for syphilis. Males were three times more likely to contract STDs (27%) than their female (9%) counterparts. Whereas knowledge on methods of prevention was high (>90%) it was not followed by appropriate behavioural patterns. More female (33.5%) students had heard about Trichomonas vaginalis than males (23%); (((2) = 17.1; < 0.0001). This study has shown that more female than male students got information from their parents (((2) = 25.3; p < 0.001) while more male students had their source of information from previous sexual intercourse (((2) = 12.9; p = 0.001). The level of knowledge about STDs and their prevention is not matched by sexual behavioural patterns, and male students undertake more risky sexual behaviour. Sexual education should be introduced at the university as a means of increasing students' awareness about the problem and prevention of sexually transmitted diseases including HIV/AIDS.