Background: The nasal mucosa is sacrificed in conventional endoscopic dacryocystorhinostomies (EDCRs). Some surgeons, however, modify the technique by elevating a mucosal flap prior to creating the osteotomy with the aim of preserving the mucosa. To our knowledge, no clear-cut benefit of a mucosal flap has been established. The aim of this study is to examine the differences in surgical techniques and success rates of EDCRs with and without mucosal flap preservation. Methods: We carried out a medical record review of all patients who underwent primary EDCR at the Goldschleger Eye Institute from October 2009 to October 2017. The following data were retrieved from the medical database and analyzed: patient demographics (age at diagnosis and gender), medical history, examination findings, surgical details, postoperative success, complications, and follow-up. Results: A total of 107 patients who underwent 117 EDCRs participated in the study. Fifty-one patients comprised the group without a mucosal flap and 56 patients comprised the group with mucosal flap preservation. The medical history, presenting complaints, and preoperative examination findings were similar for both groups. The surgical success rate was not significantly different between the groups (82.1% without flap vs. 86.8% with flap, P = 0.478, Chi-square). Conclusion: The findings of this comparison of EDCRs with and without mucosal flap preservation in a large patient population revealed no differences in surgical success or complications rates between the two procedures and, therefore, no benefit for adding flap preservation to conventional EDCRs.