Appendiceal intussusception (AI) is a difficult disease to diagnose. Various features of the disease were analyzed in a 35-year-old female patient admitted with abdominal pain and diagnosed with AI. The diagnosis was made with colonoscopy and abdominal computed tomography. Laparoscopic partial cecum resection was performed. Pathology examination revealed foci of endometriosis externa, which infiltrated the muscular layer of the appendix. AI should be kept in mind in the differential diagnosis of recurrent abdominal pain. Colonoscopy is an indispensable examination for differential diagnosis. Laparoscopic partial cecum resection, preserving the ileocecal valve, is an appropriate treatment approach in irreducible cases that are not suspected to be malignant.