Anorectum is a rare location for malignant lymphoma. Involvement of is rare even for the lynphoma associated with acquired immune deficiency syndrome (AIDS), and AIDS has a relatively increased frequency of anorectal lymphoma. Most lymphomas in AIDS patients are of a B-cell origin, and T-cell lymphoma of the gastrointestinal tract is extremely rare. We report here on a case of anorectal and gastric peripheral T-cell lymphoma, unspecified (PTCLu) in a non-AIDS patient. A previously healthy 29-year-old man presented with hematochezia and tenesmus that he had suffered with for the previous 2 months. Sigmoidoscopy showed anal and rectal submucosal tumor. Multiple round-shaped, flat and elevated lesions were noted on the gastric antrum and body as well. He underwent excisional biopsy for the anal mass and the diagnosis was PTCLu. Biopsies of the gastric lesions gave the same diagnosis. There was no lymphoma involved in the bone marrow. At admission, no antibodies against human immunodeficiency virus were detected. He underwent systemic chemotherapy and upfront autologous stem cell transplantation.