Back ground :enuresis for most children is a source of shame and anxiety with profound effect on self-perception ,relationship and school performance, hence the study of nocturnal enuresis in Tripoli city.Aim of the study: to determine the prevalence of nocturnal enuresis and identify the possible risk factors among primary school children in Tripoli city .Materials and Method : A cross sectional survey was performed between March to May 2021, the study subjects primary school children aged 6 -12 years taken randomly from 10 school in Tripoli city, A special forma questionnaire was used to collect data which included the following ,socio-demographic factors, family characteristics and factors related to the presence of enuresis. statistical analysis was done by SPSS 22 package program Results: A total 500 of primary school children with response rate 418(81.6%),the prevalence rate of enuresis are 19.6 % ,more comm. one in males, in age group from 6-8 years, and also children with birth order from 2nd to 4thwere more affected with enuresis than others, most of enuretic child were hartd awaken(16.5%),faced stressful events( 17%) , burning of micturition( 11%), and complained of other disease( 10.5%) .Conclusion: The study revealed that the prevalence of enuresis 19.6%.with a higher in boys. highe ducation level of parents,, sleeping pattern, existence stressful events, positive family history of NE, large family size, more children household and presence of other diseases especially urinary tract. May act as risk factor for NE.