The goal of this work is to analyze the different reasons of absenteeism in hospital and to identify the socioprofessional characteristics of absentees, what would permit to guide a strategy on modes and content of a preventive action. The adopted methodology is a retrospective descriptive investigation carrying on absenteeism of the personnel working in academic hospital Farhat Hached of Sousse (Tunisia) during 1997. So, on the 1433 salaried employees, 1028 (71.7%), left once or more for different reasons. The global absenteeism rate is 4.03% and the mean absence by agent is equal to 14.7 days. Among the absences motives, illness predominate extensively with 55% of the whole. Maternity and postnatal leave constitute 30%, 8% for "Industrial accidents" of work stops. Whatever is the reason, we observes more absent women than absent men. This survey shows the importance of socioprofessional factors in genesis of absenteeism and, to reduce the problem, the necessity to improve conditions of work, moreover in his ergonomic, social and psychological aspects.