For several years, quality of life is used as a measure of health status. As university constitues a specific setting for young adults, the Health Service of the french-speaking Free University of Brussels initiated a survey in order to study health behaviours of students from the first grade. During the academic year 1998-99, 3,185 students were surveyed in the first degree, using an anonymous self-completed questionnaire with the following topics: health perception, weight, social support, emotional well-being, tobacco, alcohol, medicines, cannabis and ecstasy use as well as access to general practitioner. Body Mass Index was computed and emotional well-being was approached using CES-D scale. Results are presented by gender and faculty. Mutivariate analysis was also realised using logistic regression. In general, results confirm the data resulting from other studies in general population as well as at school. Nevertheless, results show that health is a problem for a minority of students and is a "whole" that has to be approached globally. Moreover, data give a basis to define priorities and strategies to improve students' physical and mental well-being at university. Results are also useful to better target these actions to those at needs.