Chronic eosinophilic pneumonia. The chronic eosinophilic pneumonia is part of Pulmonary Eosinophilic Syndroms. It is presented a 33-years old man, Asmathic, with dry cough, fever, night sweats and fatigue of several weeks. The chest X-ray showed opacity in the right hemithorax. He was treated with antibiotics without response. A chest TC showed multifocal involvement. The patient refused bronchoalveolar lavage (BAL) so treatment antituberculostatic was started. Despite treatment the symptoms worsened. The Chest X-ray showed migration of the infiltrates and the blood smear marked eosinophilia. Finally, bronchoalveolar lavage was carried out and it showed a high percentage of eosinophils (over 50%). The patient was treated with inmmunosuppresive doses of corticosteroids with excellent response. The blood smear in Nonresolving pneumonia is key to consider eosinophilic pneumonia, an uncommon pathology but amenable to treatment.