Objective: To evaluate intraocular pressure (IOP) lowering effect and safety of Ex-PRESS® mini glaucoma drainage implant (Alcon, Fort Worth, TX) for the surgical treatment of glaucoma. Material and Methods: The data of the subjects who underwent Ex-PRESS® mini glaucoma shunt (P-50) implantation surgery in 2011 and 2012 were retrospectively reviewed. IOP before and after the treatment, visual acuity, the number of medications and complications were analyzed. Success was defined as final IOP of 6-21 mmHg with or without antiglaucomatous medications. Results: Thirty two eyes of 32 patients were included in the study. The mean age of patients and mean follow-up time were 54.43±14.56 years (range 20-77 years) and 6.34±2.95 months (range 3-16 months), respectively. Mean pretreatment IOP was 30.71±4.72 mmHg, while it was 13.21±3.51 mmHg (p<0.001) at the first week, 14.46±4.08 mmHg (p<0.001) in the first month, 14.37±2.93 mmHg (p<0.001) in the third month, 13.78±2.98 mmHg (p<0.001) in the sixth month, and 14.53±2.27 mmHg (p<0.001) in the last visit. An IOP less than 21 mmHg was achieved in all eyes in the last visit. The median value of preoperative total antiglaucomatous medications was 4.0 (3.0-5.0), however topical medications were discontinued in 81.3% of patients in the last visit. There were no complications during the follow-up period except one case of early postoperative choroidal effusion. Conclusion: Ex-PRESS® mini glaucoma shunt implantation is supposed to be an effective and safe method for the surgical treatment of glaucoma. It also helped to reduce the number of antiglaucoma medications, thus improving both the quality of life of the patients and their compliance to therapy.