Background: A gradual, cumulative degradation of retinal ganglion cells and their axons characterizes glaucoma, a group of progressing optic neuropathies that cause a distinctive look of the optic disc and a concurrent pattern of vision loss, Aim: The work's main objective was to assess the connection between the vessels density determined by optical coherence tomography angiography (OCT-A), the ganglion cell complex, and the retinal nerve fiber layer (RNFL) utilizing OCT, and the degree of visual field loss in primary open-angle glaucoma (POAG). Patients and Methods: This was observational cross-sectional research that was carried out at department of ophthalmology Banha University from September 2021 to June 2022. The research was carried out on 20 glaucoma patients and 20 Healthy individuals. Results: there was statistically substantial decrease pattern standard deviation (PSD) in control group while there was statistically substantial elevation visual field median deviation in control group compared to glaucoma group. Conclusion: The degree of visual field impairment is highly correlated with OCT-A vascular density measures. In general, these relationships are stronger than common structural measurements like RNFL and rim area. Furthermore, the degree of visual field loss is still highly correlated with OCT-A vessel density assessments. Due to these factors, OCT-A is a potential technique that will enable clinical tracking of vascular variations in glaucoma. Additionally, it may help us better understand the pathophysiology of the condition, particularly its underlying vascular mechanisms.