The majority of intestinal lymphoma is derived from B cells, and peripheral T-cell lymphoma-unspecified (PTCL-U) rarely invades the intestines and liver. We report a case of PTCL-U that invaded also the intestines and liver besides the lymph nodes, characterized by multiple irregular ulcers of the intestine and ileocecal junction, and multiple intrahepatic low density foci. The diagnosis was established by mucosal biopsy and pathological examination. This case highlights the possibility of PTCL-U involving uncommon organs, for which a definite diagnosis has to be established pathologically. PTCL-U is highly malignant with a poor prognosis, and so far no standard treatment strategy has been available.