Background: The aim of this study was to determine the relationship between primary nocturnal enuresis (PNE) and upper airway obstructive pathologies such as allergic rhinitis (AR), nasal septum deviation (NSD), adenoid hypertrophy (AD) and tonsillar hypertrophy (TH).Methods: The study included 78 volunteer PNE patients (42 males, 36 females; mean age: 7.2 ± 1.6 years, range: 5.4 to 11.6 years) who applied to Pediatrics and Urology outpatient clinics of a second-stage hospital between June 1, 2018 and September 1, 2018. The control group included 72 volunteer children (34 males, 38 females; mean age: 7.6 ± 1.4 years, range: 5.1 to 12.7 years) who were admitted to the inpatient outpatient clinics of the same hospital and had no PNE complaint. All participants included in the study were applied routine physical examination, flexible fiberoptic nasopharyngoscopy and score for allergic rhinitis (SFAR) questionnaire. Brodsky scale and fiberendoscopic findings were used to classify tonsil and adenoid dimensions respectively.Results: There was no significant difference between PNE (+) and PNE (-) groups in terms of age and gender (respectively p = 0.203 and p = 0.819). Although AR and NSD were similar in both groups, the ratio of AH and TH was statistically significantly higher in the PNE (+) group (p = 0.016 and p = 0.05, respectively). Conclusion: Adenotonsillar hypertrophy must be considered in children with primary nocturnal enuresis.