Ascariasis can be found in temperate and tropical areas but is more prevalent in most of the inter tropical zone due to local socio-economic conditions.Loeffler’s syndrome,also known as eosinophilic pulmonary syndrome is due to the trans-alveolar migration of ascaris larvae about 2 weeks after initial oral contamination.In this article, the case of a 10-year old child referred by his pediatrician for isolated eosinophilia,who was finally diagnosed with to have Loeffler’s syndrome is presented and discussed. Ascariasis can be found in temperate and tropical areas but is more prevalent in most of the inter tropical zone due to local socio-economic conditions. Loeffler’s syndrome, also known as eosinophilic pulmonary syndrome is due to the trans-alveolar migration of ascaris larvae about 2 weeks after initial oral contamination. In this article, the case of a 10-year old child referred by his pediatrician for isolated eosinophilia, who was finally diagnosed with to have have Loeffler’s syndrome is presented and discussed.