We experienced a case of giant localized fibrous pleural mesothelioma accompanying lung metastasis. The patient was a 26-year-old woman, who was pointed out elevation of the left diaphragma by the chest roentgenogram in 1992 but left it as it was. In 1995, a giant tumor occupying 1/2 or more of the left thoracic cavity was detected by chest CT and MRI. A giant localized pleural mesothelioma was suspected since there was no accumulation in Ga scintigram and an operation was performed. The tumor originated without pedicle and with invasion of the lung from the pleura of the left S8 and it was excised by separating the left lower lobe at 7-cm distance from the tumor. The tumor was 20 x 12 x 11 cm in size weighing 1700 g and the histopathological diagnosis was localized fibrous pleural mesothelioma. A lung metastasis of 1.0 cm in size was found in a part of the left lower lobe resected at the same time. The postoperative course has been satisfactory and there is no sign of recurrence at present. There are occasional cases of recurrence associated with a localized fibrous pleural mesothelioma even though it is judged benign. In the present case, a metastatic focus was already present at the time of initial surgery and is considered a valuable case.