Pin worm is a nematode distributed worldwide. It infects all ages and sexes especially children, but the infection is still of a very little of concern. Different diagnostic methods were used for investigating Enterobius vermicularis prevalence in 1020 patients (500 male and 520 female) in Kirkuk city. Stool samples were collected and proceeded for General Stool Examination (GSE).The overall incidence of E. vermicularis was 34.6 %. A rate of 5.3% was detected microscopically, 5.9% by swab method, 26% by cellophane tape and 41% macroscopically by detecting the larva and adult worm with naked eye. The worm was prevalent in all ages. High rate (27%) of infested person has been infected for 7-10 years. Significantly strong relation had appeared between E. vermicularis infection and appendicitis and fallopian tube obstruction. 49.5% of infected individuals had appendicitis and 27.4% had fallopian tube obstruction, a rate of 48.4% of tubular obstructed women were infertile.12.2% of E. vermicularis infected patients had Urinary Tract Infection (UTI). All used anti-helminthic drugs were not effective against the infection. The conclusion is: high percentage of Kirkuk population is infected with E. vermicularis but most of these cases were not diagnosed. E. vermicularis infection can led to appendicitis or tubular obstruction especially in chronic cases. Therefore, parents are recommended to treat their children, especially females as soon as they recognize the infection, to preserve the future complications that might be caused by the worm as fallopian tube obstruction and infertility.