Recently we have experienced one case of pulmonary lymphangioleiomymatosis(LAM). A 49 year-old woman visited the outpatient department complaining of longstanding dyspnea, which was aggravated by exercise. Although the chest PA film showed nothing more than a slight increase in interstitial marking, a lung HRCT revealed multiple cystic lesions of a similar size that were scattered through out the whole field in both lungs. An abdominal CT detected an angiomyolipoma located in the midbody of the left kidney. Video-assisted thoracic surgery(VATS) was performed for the pathologic diagnosis. On gross examination of the biopsy lung, a pulmonary LAM was confirmed by a finding of smooth muscle proliferation in the interstitum of the lung. After the final diagnosis, oral medroxyprogesterone was prescribed and she is presently in a stable condition.