To compare the efficacy of gonioscopy-assisted transluminal trabeculotomy combined with cataract surgery (PGATT) and trabeculectomy combined with cataract surgery (PTRAB) in open-angle glaucoma patients.A multi-centered, retrospective, non-randomized study included 67 PGATT patients and 70 PTRAB patients. We compared preoperative intraocular pressure (IOP), best-corrected visual acuity (BCVA) compared with early and final IOP, medication numbers, and BCVA levels. Success was determined as IOP reduction 20% from baseline, IOP between 5 and 21 mmHg, preoperative IOP of higher than 21 mmHg with medication and postoperative IOP of less than 21 mmHg without medication for surgeries performed for intolerance to medication, postoperative IOP 21 mmHg as well as 18 mmHg separately without medications, and no need for further glaucoma surgery.Preoperative IOP values were 28.61 ± 6.02 mmHg in PTRAB group and 23.99 ± 8.00 mmHg in PGATT group (P 0.0001). Early postoperative IOP values were found lower in PTRAB group as 12.19 ± 3.41 mmHg and as 15.69 ± 4.67 mmHg in PGATT group (P 0.0001). Last follow-up IOP reading were lower in PGATT group (P = 0.009). IOP difference values were found higher both in early and last postoperative periods in PTRAB group (respectively, P 0.0001, P = 0.018). Success rates were found higher in both at lower than 21 and 18 mmHg levels in PGATT group (respectively, P = 0.014, P = 0.010).We found the PGATT combined procedure to be a well-tolerated, effective procedure that can lower IOP both early and late in the postoperative period with different rates of IOP success compared with the combined PTRAB procedure.