Hydatid disease remains a serious health problem for the Mediterranean countries, such as Turkey. At present Hydatid cyst is an endemic public health problem that is seen especially in some parts of South America, Middle Asia and South Europe. Pleural hydatid cyst is seen rarely and is supposed r to depend on rupture of pulmonary or liver hydatid cysts. A nineteen year old man who took part in sports and was previously completely healthy was admitted to the emergency service with chest pain that began suddenly and was not improving with rest. Thorax tomography was planned because a circular opacity with a 5 cm diameter is seen in pulmonary radiography of the patient. In the thorax tomography, there was a supported t hydatid cyst image with pleural invasion into the right middle lobe of the lung (pulmonary). The patient was operated on by thoracic surgeons. On the fifth day, the patient was discharged from hospital. Hydatid cysts infect different tissue including the pleura. In emergency service, physicians should notice that the patient with atypical chest pain and pulmonary opacity site in radiography may have a pleural cyst hydatid cyst.