Two patients with pulmonal Echinococcosis are presented by the authors. Contact with cestoda carrier animals cannot be revealed. At the first patient, who was without any complaints, the two round shadows in her chest X-ray were detected accidentally by screening examination and before the operation only eosinophilia, many eosinophil granulocytes in the pleural effusion and the positive complement binding reaction were related to the Echinococcosis, which was proved by the histological examination of the intraoperative biopsy. The other patient had complaints during months. In this case the Echinococcus granulosus broke into the bronchus and emptied in the sputum. Postoperative histological diagnosis can be obtained by help of the excision from the intraluminal alteration which was visible during bronchoscopy. The authors summarize the etiology, the clinical signs, the diagnose and the therapy of Echinococcosis. They call attention to the incidence of this mainly tropical disease in Hungary and to the rare soliter pulmonal manifestation of the Echinococcosis.