The purpose of this study is to analyze the eye comfort of the aeronautical personnel. This study has been conducted in ophthalmologic office of the National Institute of Aeronautical and Space Medicine, for 68 patients (group 1), men and women, active aeronautical personnel, between 35-55 years old, apparently ophthalmologically normal subjects. First the patients filled out a questionnaire that was intended to provide the subjective evaluation; objective investigation included: biomicroscopy, fluorescein stain, tear break up time (BUT) and Schirmer tear test. There have been found subclinical, mild and moderate dry eye; tear substitutes have been prescribed. The patients were re-examined every 3 months, for a period of 9 months. Results were compared with those obtained from a control group--20 people (group 2), women and men, with ages in the same range, people not involved in the aviation field who requested ophthalmological examination for optical correction. The results raise the question: can the "Dry eye syndrome" be considered a work-related disease? The answer will be "probably no" indulging oneself conditions required by International Aeronautical Authority (ex. periodically hydration and enough in volume), even if the environmental conditions inside the aircraft can produce this disorder. During flight, aeronautical personnel should use tear substitutes, because of the low humidity of the air inside the aircraft.