A 66-year-old male was admitted to our hospital complaining of bilateral hypochondrial pain, back pain and loss of weight in May, 2002. Superficial lymph nodes were not palpable on admission. The leukocyte count was 3430/microl, hemoglobin concentration, 13.0g/dl, and platelet count, 174000/microl. LDH, soluble IL-2 receptor, ACTH and cortisol values were out of the normal range (LDH 1368IU/l, sIL-2R 2630U/ml, ACTH 132pg/ml, cortisol 7.4microg/dl). Abdominal CT scan showed bilateral adrenal masses, and abnormal uptake of Ga-scintigraphy was seen correspondent with the bilateral adrenal masses. The histological diagnosis of bilateral adrenal masses cannot be performed because of the bleeding tendency, but atypical cells were observed in the patient's bone marrow aspirate. Surface marker analysis of atypical cells showed CD5+, cyclin D1+, CD19+, CD20+ and HLA-DR+. From these results we diagnosed this case as a mantle cell lymphoma (stage IV B) markedly infiltrated into the adrenal glands with adrenal insufficiency. The bilateral adrenal masses dramatically reduced in size after CHOP chemotherapy with hydrocortisone supplementation. We report on the present case and summarize the reports of adrenal grand-infiltrating lymphomas.