PURPOSE: To assess a model combining optical coherence tomography angiography (OCTA) and optical coherence tomography (OCT) parameters to predict the severity of paracentral visual field (VF) loss in primary open-angle glaucoma (POAG). DESIGN: Cross-sectional study. PARTICIPANTS: Forty-four patients with POAG and 42 control subjects underwent OCTA and OCT imaging with a swept-source OCT device. METHODS: The circumpapillary microvasculature was quantified for vessel density (cpVD) and flow (cpFlow) after delineation of Bruch's membrane opening and removal of large vessels. Retinal nerve fiber layer thickness (RNFLT) and Bruch's membrane opening-minimum rim width (BMO-MRW) were measured from structural OCT. Paracentral total deviation (PaTD) was defined as the average of the total deviation values within the central 10 degrees on Humphrey VF testing (24-2) for upper and lower hemifields. The OCT and OCTA parameters were measured in the affected hemisphere corresponding to the hemifield with lower PaTD for POAG patients. Models were created to predict affected PaTD based on RNFLT alone; RNFLT and BMO-MRW; OCTA alone; or RNFLT, BMO-MRW and OCTA parameters. The models were compared using coefficient of determination (r2) and Bayesian information criterion (BIC) score. BIC decrease of ≥6 indicates strong evidence for model improvement. MAIN OUTCOME MEASURES: Performance of models containing OCT and OCTA parameters in predicting PaTD. RESULTS: POAG and controls were similar in age and gender (65.9±9.5 years and 38.4% male overall, p≥0.56 for both). Average RNFLT, minimum RNFLT, average BMO-MRW, minimum BMO-MRW, cpVD, and cpFlow were all significantly lower (all p<0.001) in the affected hemisphere in POAG patients compared to controls. In POAG patients, the average mean deviation was -4.33±3.25 dB; the PaTD of the affected hemifield averaged -4.55±5.26 dB and correlated significantly with both OCTA and structural OCT parameters (r≥0.43, p≤0.004 for all). The model containing RNFLT, BMO-MRW, and OCTA parameters was superior in predicting affected PaTD (r2=0.47, BIC=290.7), with higher r2 and lower BIC compared to all three other models. CONCLUSIONS: A combined model of OCTA and structural OCT parameters can predict the severity of paracentral visual field loss of the affected hemifield, supporting clinical utility of OCTA in POAG patients with paracentral VF loss.