Kikuchi's disease is a benign self-limiting necrotizing lymphadenitis that occurs most commonly in young women, and is usually found in the cervical lymph nodes. When there is an unusual location of involved lymph nodes, the diagnosis can be difficult. We recently treated a patient with Kikuchi's disease who had ileocecal mesenteric lymph node involvement; the patient presented with symptoms of acute appendicitis in an 11-year old boy. Although mesenteric lymph node involvement of Kikuchi's disease is very rare, Kikuchi's disease should be added to the differential diagnosis of acute appendicitis in patients with enlarged ileocecal mesenteric lymph nodes on radiological evaluation.