Background: choanal atresia is one of congenital anomalies that needs surgical repair. Nasal re-stenosis and obstruction are side effects of endoscopic repair. Mitomycin was proposed to decrease postoperative stenosis and/or obstruction. Aim of the Work: it was to address the efficacy of adjuvant mitomycin therapy application in providing the postoperative patency in choanal atresia. Patients and Methods: this study is a record analysis of surgical outcomes of transnasal endoscopic surgical choanal atresia repair in Al-Azhar University Hospitals (Cairo and Damietta). The study included records of 30 children with either uni- or bi-lateral choanal atresia. Eighteen (18) children of themwereoperated upon with adjuvant mitomycin therapy. Meanwhile, records of 12 children were operated uponwithout adjuvant mitomycin andconsidered as a comparison group. Postoperative stenting was carried out in all participants. The collected information included demographic information, associated co-morbidities, operative details, and endoscopic findings. The outcome measures were: granulation tissue formation, need for postoperative dilation and need for revision surgical intervention. Results: re-stenosis was reported in 11 (28.9%) patients. The need for revision surgery was reported in 10.3%. The postoperative dilatation was required in 10 (25.6%) patients, and there was no significant difference between mitomycin and comparison groups. Conclusion and Recommendation: the use of adjunctive mitomycin therapy with endoscopic repair of choanal atresia seems to be effective and safe approach. Multicenter follow up trials should be done to fully evaluate the value (benefits) of adjuvant mitomycin therapy in choanal atresia repair.