Background: Congenital nasolacrimal duct obstruction is frequent and paediatric endonasal endoscopic dacryocystorhinostomy (DCR) is increasingly used after conservative treatment failure. Methodology: Retrospective noncomparative case series study was conducted from January 2007 to August 2017. Patients under 18 years old with nasolacrimal system obstruction who underwent endoscopic DCR were studied. All children were referred to our otorhinolaryngology department in a tertiary referral paediatric hospital. Population characteristics, presentation symptoms, success rate and predictive factors for failure were analysed. Results: 30 children were identified. Ages varied from 2 to 13 years old. Simultaneous bilateral surgery was performed in 5/30 (16,7%) children. Silicone stents were used in 93% of interventions with a mean time to removal of 9,6 weeks. Persistent epiphora was found in 43% of children and recurrent dacryocystitis in 57%. Success rate for primary DCR was 83,3%. Revision surgery was performed in 16,7% of cases. Minor complications rate was 13,3%. The presence of concomitant chronic nasal infections pointed for surgery failure reaching statistical significant value (p=0.0456). Conclusions: Paediatric endonasal endoscopic DCR seems to be an effective, safe and minimally invasive technique for the treatment of mechanical nasolacrimal system obstruction.