An 81-year-old woman was admitted to our hospital because chest X-ray imaging indicated large tumorous shadows in the right middle and lower lung fields. She exhibited no symptoms or physical signs. Chest CT showed a 35.6×22.4 mm mass in S⁴ and a 50.9×33.2 mm mass in S⁸ in the right lung. Her serum ATLA-antibody level was ×8,192, and the soluble interleukin-2 receptor was 5,852 U/ml, suggesting adult T-cell leukemia lymphoma (ATLL). Cytology of a CT-guided biopsy specimen from the S⁸ tumor showed incised and segmented nuclei. Histopathology indicated moderately enlarged atypical lymphocytes; immunohistology showed that the tumor was negative for anaplastic lymphoma kinase, and positive for a cluster of differentiation 4 (CD4), CD25, and CD30. Based on these findings, we diagnosed this case as ATLL. Thus we report a rare case of ATLL presenting with large pulmonary masses without ground-glass shadow, centrilobular nodules, septal lines, infiltration, and bronchiectasis, suggesting that ATLL is one of the differential diagnoses for large pulmonary tumors.