Aim: To compare the efficacy of endoscopic cyclophotocoagulation (ECP) vs repeat transscleral cyclophotocoagulation (TCP) in eyes with persistent glaucoma despite prior treatment with TCP. Materials and methods: This was a retrospective chart review of glaucoma patients at the American University of Beirut Medical Center over 10 years who underwent ECP or repeat TCP. We reported qualified and complete success; success was defined as postoperative intraocular pressure (IOP) ≤21 mm Hg, with (qualified) or without medications (complete) and without procedure-related complications. Results: This study included 23 eyes of 21 patients with various forms of uncontrolled glaucoma who had failed TCP. A total of 13 eyes of 12 patients underwent ECP with a mean age of 39.9 ± 23.2 years, and 10 eyes of nine patients underwent repeat TCP with a mean age of 27.2 ± 22.6 years. A significant decrease in IOP was observed from 38.5 ± 7.9 mm Hg preoperatively to 25.2 ± 8.8 mm Hg postrepeat TCP (p = 0.006) and from 33.0 ± 9.5 to 12.8 ± 3.9 mm Hg post-ECP (p < 0.001), noted at a mean follow-up time of 39.2 ± 44.4 and 41.5 ± 37.4 months, respectively. The mean number of antiglaucoma medications decreased in the two groups (from 3.8 ± 1.0 preoperatively to 1.8 ± 0.9 postoperatively for ECP and from 3.5 ± 1.3 to 3.1 ± 0.9 postoperatively for TCP); however, the drop was only statistically significant post-ECP. Qualified success was significantly higher after ECP vs repeat TCP (91.7 vs 40%, respectively). Complete success was achieved only in 1/12 (8.3%) eyes in the ECP group. Conclusion: Endoscopic cyclophotocoagulation (ECP) performed in glaucomatous eyes previously treated with transscleral cycloablation provided more IOP control as compared to repeat TCP by directly treating viable tissue in previously skipped ciliary processes and in between processes. Clinical significance: In glaucomatous eyes previously treated with transscleral cycloablation, ECP attained better IOP control than repeat transscleral cycloablation.