The tear film was evaluated by the ferning test. We tested tear film in right and left eye on 28 subjects (total 56 eyes), of whom 14 were affected by Down's syndrome, age range 18 to 35 years. The results obtained show that there exists an alteration of the tear ferning in subjects affected by Down's syndrome. We did not find any difference between the right or left eye in each individual. This anomaly could be responsible for frequent infectious pathologies found in the anterior eye segment in these subjects.