We report two cases of pulmonary lymphomatoid granulomatosis that showed diffuse ground-glass opacities in the course of illness. In the first case, an 85-year-old man was admitted with multiple nodular shadows in both lung fields. After admission, an HRCT scan showed diffuse ground-glass opacities. These shadows improved after steroid therapy, but he ultimately died of uncontrollable infection. The diagnosis of lymphomatoid granulomatosis was made from histological findings of the autopsy. In the second case, a 71-year-old man was admitted with multiple nodular shadows in both lung fields. We diagnosed lymphomatoid granulomatosis based on the findings of a thoracoscopic lung biopsy. The nodular shadows improved after R-CHOP chemotherapy, but his HRCT scan was complicated with diffuse ground-glass opacities after the treatment. Although steroid therapy was performed, he died of uncontrollable infection.