Background: The purpose of the present study was to compare the clinical features and the surgical approaches of the pulmonary hydatid cysts in children and adults. Methods: One hundred and thirty-four patients, operated on for pulmonary hydatid cysts over the last 10 years were retrospectively evaluated in two groups: 39 children who were younger than 18 years old (29%) and 95 adults (71%). The patients in each group were analysed according to their clinical, radiological and surgical findings. Results: The frequency of pulmonary hydatid cysts in children was significantly higher in boys (74%) than in girls (26%). However, there was no sex tendency in adults (52% in male vs 48% in women). The sex difference in hydatid cyst frequencies between adults and children was significant (P < 0.05). Among preoperative pleural complications, pneumothorax (15.5%) in children and empyema (11%) in adults were more frequent. The frequency of concomitant hepatic cysts was less in children than in adults (33% vs 79%). Huge pulmonary cysts (=10 cm) were more common in children (31%) than in adults (22%). Cystotomy with capitonnage was the most frequently preferred method in both groups. Postoperative complications developed in six children (16%) and 19 adults (19%), and were more frequent in patients with huge cysts (27% vs 16%). No recurrence was observed in both groups. Conclusions: Isolated pulmonary cysts are more common in children than adults. The cysts also tend to be bigger in children than adults. The frequency of concomitant hepatic cysts is less in children. Because of higher lung expansion ability and improvement capacity in children, resection should be avoided and lung saving surgical procedures should be performed. In spite of differences observed in the clinical features it does not change the treatment of pulmonary hydatid cysts in children.