We report the case of a 33-year-old woman who had visited our hospital at the age of 20 years with a chief complaint of chest pain, and by computed tomography (CT) we found her to have bilateral, diffuse, multiple pulmonary cysts. An examination of surgical lung biopsy samples at that time showed accumulation of S100 protein-positive Langerhans-cells. No lesions were seen outside the lungs, and she was diagnosed as pulmonary Langerhans-cell histiocytosis. The patient stopped smoking from the time of diagnosis, and although partial improvement was observed, the multiple cysts persisted. The patient became pregnant and gave birth twice, 9 and 11 years after diagnosis, with no maternal complications. Although there have been a few reports of pregnancy and childbirth in patients with pulmonary Langerhans-cell histiocytosis, such cases are associated with many complications. This patient is reported because two successful pregnancy results with no maternal complications are rare in such cases.