A 69-year-old man who had undergone right upper lobectomy for pleomorphic lung carcinoma (T1bN0M0; stage IA) 7 months earlier was admitted to our hospital complaining of repeated right lower abdominal pain for about a month. Enhanced CT scan showed a mass close to the appendix, and abscess formation caused by acute appendicitis or tumorous lesion was suspected. Emergency ileocecal resection with D2 lymphadenectomy was successfully performed without rupture of the abscess. Histopathological examination indicated appendiceal metastasis from pleomorphic lung carcinoma. Although appendiceal metastasis from lung carcinoma is rare, the possibility of this state should be considered in order to improve the prognosis in patients with a past history of poorly differentiated lung carcinoma.