To find out prevalence of enuresis nocturna (EN) among school age children, and to determine associated factors and regional differences, an epidemiological study was performed among children between 7 to 12 years living in Zonguldak, Turkey. Data were collected at schools by a questionnaire. EN prevalence was found as 8.9 %, most (75.7 %) were primary, and the rest were secondary. Prevalence decreased as the age increased in both genders. There was a positive relationship of EN with positive family history, presence of EN in a brother or a sister, encopresis, sleep disturbances, a maternal education of primary school or less, working mother, low monthly income, low school success and introversion or extroversion. Only 19.8 % of the cases preferred medical treatment modalities, other preferences were waiting for spontaneous improvement, awaking the child for voiding, water restriction and diapering, in decreasing order. As EN is a disease that can result in low self-esteem, some other psychological problems and low school success, it must be treated. Informing these parents wherever they are met, especially at primary health care settings, is necessary both not to miss patients and to convince the parents for treatment.