Objective To compare the clinical efficacy between Ex-PRESS glaucoma shunt implantation and trabeculectomy in primary open angle glaucoma (POAG). Methods Forty-eight eyes of 27 patients with POAG were randomly divided into Ex-PRESS glaucoma shunt group, 24 eyes of 14 patients, and trabeculectomy group, 24 eyes of 13 patients in prospective study. The intraocular pressure, visual acuity, visual field and retinal nerve fiber layer thickness (RNFLT) before and after surgery were recorded. Results The differences in the intraocular pressure were not significant statistically(F=0.448, P=0.507)between the two groups preoperatively and postoperatively 1 week, 1 month and 3 months. There was no statistically difference in visual acuity between the two groups at preoperatively, 1 week, 1 month and 3 months postoperatively(Z=-1.076, -0.922, -0.513, -0.640; P=0.282, 0.357, 0.608, 0.522). The difference in RNFLT, absolute value of mean defect and pattern standard deviation 3 months postoperative compared to preoperative were not statistically significant(P>0.05). Conclusion Ex-PRESS glaucoma shunt implantation and trabeculectomy have similar clinical efficacy in POAG.The cost-effectiveness ratio should be taken into account when deciding which approach is better. Key words: Glaucoma, open-angle, primary; Implantation, glaucoma shunt, Ex-PRESS; Trabeculectomy; Intraocular pressure