We describe a patient with acquired immunodeficiency syndrome who presented with acute appendicitis but was found to have angiotropic large cell lymphoma (ALCL) by pathologic examination of the appendectomy specimen, without acute inflammation. Very rare cases of angiotropic large cell lymphoma have been reported in patients with human immunodeficiency virus infection, and most cases of this rare lymphoma are of B-cell origin, but in this instance immunohistochemical analysis showed a T-cell phenotype.