Purpose To determine the effect of Primary Open Angle Glaucoma (POAG) on visual function and Quality of life (QOL) in patients attending the Guinness Eye Centre (GEC) Lagos University Teaching Hospital (LUTH) Idi-Araba. Methods One hundred and thirty two consecutive patients with varying degrees of severity of POAG and 132 age and sex-matched controls with corrected refractive errors and no family history of glaucoma at GEC were enrolled into the study. POAG patients for the study were defined as patients with gonioscopically determined open anterior chamber angles, pale and cupped discs (Cup: Disc ratio >0.4), corresponding visual field defects with or without an elevated IOP. They underwent a comprehensive ophthalmic examination which included visual acuity, intra-ocular pressure measurement, dilated funduscopy, gonioscopy and visual field assessment by standard automated perimetry. The mean deviation (MD) was used to classify glaucoma patients into mild, moderate and severe glaucoma. Colour vision and contrast sensitivity were assessed using the City University Online test and the Pelli-Robson Chart. Stereopsis was assessed with the TNO stereotest. QOL was assessed using the 25 item National Eye Institute Visual Function Questionnaire (NEIVFQ25) and the Glaucoma Quality of Life-15 questionnaire (GQL-15). Data was analysed using Software Programme for Social Sciences (SPSS) version 15. Correlation, univariate and multivariate regression analysis of data was carried out to test for statistical significance.