Introduction:Sleep disorders are common in the hospital setting. The objective of our study was to identify factors responsible for an alteration of sleep quality in hospitalized patients.Methods: Cross-sectional, comparative study including two groups of patients hospitalized in the pneumology (G1) and emergency (G2) departments of La Rabta Hospital in Tunis.Results :During the study period, 95 patients (G1: n=47, G2: n=48) were included. Hospitalization was the cause of sleep disorders in 93.7% of patients. Individual factors associated with sleep disorders in hospital were coffee consumption, pain, anxiety and history of chronic respiratory disease (for G1 patients). The hospital conditions associated with sleep disorders were noise, light, room neighbour, paramedical care and hygiene conditions.Conclusion :Sleep disturbances are common in the hospital setting. The factors responsible were individual and related to the conditions of hospitalization.