Histopathological examination of the appendix after appendectomy is routinely performed. The object of this systematic review is to determine whether routine histopathological examination of the appendix is justified. PubMed, EMBASE, Web of Science and the Cochrane library were searched without language restriction up to 1 October 2009. All articles that reported on the incidence of histopathologically proven aberrant appendiceal pathology were included. Nineteen case series reported the incidence of a benign neoplasm [0.5%, weighted mean (WM)], malignant neoplasm (0.2%, WM) and other pathology (0-14%). Nine articles reported the sensitivity of the intra-operative findings to detect aberrant diagnoses. Parasitic infection was detected in 0-19%, endometriosis in 0% and granulomatosis in 0-11% of cases. Five articles addressed the consequences of aberrant pathology. Most patients with parasite infection, granulomatosis and malignant neoplasms underwent additional investigation or treatment, in contrast to patients with a benign neoplasm. The incidence of unexpected findings in appendectomy specimens is low and the intra-operative diagnosis alone appears insufficient for identifying unexpected disease. The benefit of histopathology is studied inadequately. From the present available evidence, routine histopathology cannot be judged as useless. © 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.