Purpose: Studies on patients with nasolacrimal duct obstruction have suggested the presence of comorbid allergic rhinitis. This study aimed to investigate the role of allergic rhinitis in the long-term surgical failure of diode laser dacryocystorhinostomy. Materials and methods: A total of 153 patients undergoing diode laser dacryocystorhinostomy between 2013 and 2017 were included in the study. In the consultation and follow-up, a skin prick test, endoscopic nasal examination, and nasal symptom scoring were performed. Results: A total of 137 patients participated in the follow-up. The nasolacrimal obstruction complaints were completely resolved in 112 patients (81.8%). Of these, eight (7.1%) had positive skin prick tests. The preoperative complaints continued postoperatively in 25 (18.2%) patients. Nasal endoscopy revealed synechiae in one of these patients, whereas no anatomic deformities were observed in the other 24 patients. Of the 25 patients, 21 (84%) had positive skin prick tests. Those patients had signs of allergic rhinitis on endoscopic examination and high nasal symptom scores. There were significant differences in skin prick test results and nasal symptom scores between the two groups (p < 0.05). Conclusion: Allergic rhinitis may affect the success of dacryocystorhinostomy in patients with nasolacrimal duct obstruction. To increase the chances of surgical success, besides choosing the appropriate surgical procedure, it may be useful to treat allergic rhinitis pre- and postoperatively.