Purpose: To compare the efficacy of the microwave pulse diode laser and argon laser trabeculoplasty in primary open angle glaucoma.
 Study Design: Quasi experimental study.
 Place and Duration of Study: Shaheed Mohtarma Benazir Bhutto Medical College Lyari and Sindh Government Lyari General Hospital, Karachi, from October, 2017 to March, 2018.
 Material and Methods: One hundred and sixty patients, between 42 to 61 years with visual acuity of perception of light to 6/36 were enrolled. Patients diagnosed with POAG were included and patients with intraocular pressure of more than 40 mm Hg, previous glaucoma surgery or laser treatment and narrow angle on gonioscopy were excluded. Ophthalmic examination included visual acuity, slit lamp examination, fundus examination and visual field status using Humphrey perimeter. Patients were divided into two groups. Group A received microwave pulse diode laser (810) and Group B received argon laser trabeculoplasty. Average follow up period was 6 months. Success was assessed objectively by measuring intra ocular pressure and subjectively by visual acuity.
 Results: The average time-period for each procedure was 15 ± 5 minutes. In Group A, mean IOP at first week, first month, third month and sixth month was 20.79, 16.34, 16.21and 16.09 mm Hg respectively. While in Group B, IOP at first week, first, third and sixth month was 16.52, 15.76, 13.62, and 12.54 mm Hg at (P < 0.001 in both groups).
 Conclusion: Both microwave pulse diode laser and argon laser trabeculoplasty are effective in lowering intra ocular pressures in patients with primary open angle glaucoma.