We discuss a case of diffuse pulmonary meningotheliomatosis (DPM) resembling multiple pulmonary metastases from thyroid cancer．A 66-year-old Japanese female visited our hospital for the interpretation of abnormal shadowing on chest X-ray．High-resolution chest computed tomography revealed multiple bilateral micronodular shadows．A thyroid tumor was also detected and she was pathologically diagnosed with papillary thyroid cancer．Video-assisted thoracic surgery was performed to diagnose the pulmonary lesions, and pathologic examination of surgical specimens finally revealed minute pulmonary meningothelial-like nodules (MPMNs)．MPMNs are micronodules, most of which are detected incidentally，and the occurrence of multiple bilateral MPMNs is termed diffuse pulmonary meningotheliomatosis, which is rarely seen．On detecting multiple pulmonary nodular shadows together with a malignant disease, the possibility of DPM should be borne in mind besides pulmonary metastasis.