According to the results of studies in humans and animals - which have shown some positive influence of garlic on their immune systems – we have undertaken a similar pilot investigation in children with recurrent infections of respiratory tract and mild cellular immunodeficiency. 15 children aged 3-15 years were given a preparation of dry garlic in tablets (Aliofil) for 10 days in 3 following months. Clinical and immunological investigations were carried out before and after the treatment. Statistically significant improvement of T lymphocytes function (p=0.005), evaluated by the blastic transformation method, as well as the improvement of children clinical condition were obtained. Other investigated immunological parameters remained unchanged.