Background and objective: Needle stick Injury (NSI) is a risk in some occupations. With attention to high prevalence of viral hepatitis in general population in our country, NSI is able to transmit of this virus in society. Furthermore, because of straight exposure to rubbish, cleaner are more susceptible to this risk. The aim of this study was determination of prevalence of NSI and its risk factors in Tehran manipulators personnel.Materials and methods: This was a cross sectional study. 3127 subjects were selected from personnel of Tehan manipulator organization in 2005(1384). All subjects were assessed for demographic data, hepatitis risk factors and health history. Result: From all subjects, 15 persons (0.5%) had history of NSI. NSI was more prevalent in cleaners (16.2%) than non cleaners (0.2%) (P=0.001). Prevalence of NSI was higher in subjects who were less educated (P=0.030), with previous icter (P=0.01), self report of hepatitis (P=0.001), history of hepatitis in relatives (P=0.001) and history of liver diseases in relatives (P=0.004). There was no significant correlation between NSI and age (P=0.863), sex (P=0.980) and smoking history (P=0.356).Conclusion: Cleaners are at a higher risk of NSI (relative risk=81). This study showed that low education is a risk factor for NSI. Higher Previous history of icter, self report of previous hepatitis, history of hepatitis in relatives and history of liver diseases in family member may be causes of infection with viral hepatitis in these subjects that needs further study. On the basis of this study, more attention to put off sanitary rubbishes, education of persons at higher risk of exposure and screening programs seems to be necessary.