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Abstract Background and objectives: some parasites especially Enterobius vermicularis and helminthes are the leading factor causing appendicitis. We did this study to determine the prevalence of infection with Enterobius vermicularis among excised appendices in Necoii hospital of Qom, Iran (2005-2006). Material and Methods: In this Cross-sectional Retrospective study, we referred to pathology district archive of Necoii hospital of Qom to collect the demographic data of 3420 appendectomy patients including gender, age and infection to Enterobius vermicularis. These patients had been undertaken appendectomy from March 2005 to March 2006. After confirm of infection, all patients demographic data and histopathological results were analyzed by using Chi-square test in SPSS version 11.5 software. Results: of 3420 appendices, 17 cases (0.5%) are infected with Enterobius Vermicularis. Thirteen of them (76.5%) are female and four (23.5%) male. also 15 of infected appendices (88.2%) don’t show any pathological changes and two cases (11.8%) have appendicitis. The highest infection rate is observed in 6-10 (41.1%) and 11-15 (35.3%) age groups. Conclusion: The results show that Enterobius vermicularis does not play a role in causing appendicitis, and its presence in excised appendix can not be a good reason for being the cause of appendicitis. Key words: Appendicitis, Enterobius vermicularis, Qom, Iran