Abstract: Objective To observe the efficacy of phacoemulsification combined with endoscopically controlled goniosynechialysis for angle-closure glaucoma co-existing cataract. Design Perspective case series. Participants 53 patients (55 eyes) with chronic angle-closure glaucoma and cataract were recruited. Methods After intraocular lens implantation, injection of a viscoelastic material was used to open the synechial anterior chamber angle. Then, an endoscope was used to observe the extent of angle-closure and blunt dissection was used to re-open the rest synechial angle. The extent of the synechial angle after the first and second goniosynechialysis was analyzed statistically. The follow-up time after surgery was 3 months. Main Outcome Measures Best corrected visual acuity, intraocular pressure(IOP), closed range of anterior chamber angle. Results After the first viscoelastic goniosynechialysis, 13 of 55 eyes (23.6%)were totally opened, 1~3 hour-clocks close in 13 eyes (23.6%), 4~5 hour-clocks close in 16 eyes (29.1%), the closed extent more than 6 hour-clocks in 13 eyes (23.6%).  After the second endoscopically controlled goniosynechialysis, 24 of 55 eyes (43.6%) were totally opened, 1~3 hour-clocks close in 23 eyes (42%), 4~5 hour-clocks close in 4 eyes (7.2%), the closed extent more than 6 hour-clocks in 4 eyes (7.2%). The mean preoperative IOP was 25.6 ± 10.9 mmHg while that of the last follow-up was 15.7±6.3 mmHg(P=0.000). C/D ratio positively correlated with the numbers of angle colsed hour-clocks after the first goniosynechialysis (r=0.892, P=0.000). The local antiglaucoma medications were (3.0±0.7) kinds before surgery, while only one patient needed 2 local antiglaucoma medications after the surgery.  Conclusions Endoscopically controlled goniosynechialysis during phacoemulsification can significantly improve the success rate of goniosynechialysis for angle-closure glaucoma existing cataract. An endoscope allows the surgeon to observe the angle structures more conveniently. (Ophthalmol CHN, 2014, 23: 18-21)