In military aviation, fighter pilots are exposed during their operational missions to a maximum number of aeronautical constraints, such as altitude hypoxia, GZ+ acceleration, barotrauma and sensory illusions in flight, where the slightest physical, physiological and/or psychological deficiency can threaten flight safety or even the pilot's life. Hence the importance of a pre-flight medical check-up, especially as a preventive measure.The aim of our study was to determine the main medical causes of unfitness for military flying. It is the first study of its kind in Tunisia.