To determine the relationship between baseline retinal-vessel calibers computed by a deep-learning system (DLS) and the risk of normal tension glaucoma (NTG) progression.Prospective cohort study.Three hundred and ninety eyes from 197 NTG patients were followed up for at least 24 months. Retinal-vessel calibers (central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE)) were computed from fundus photographs at baseline using a previously validated DLS. Retinal nerve fiber layer (RNFL) thickness and visual field (VF) were evaluated semiannually. Cox proportional-hazards model was used to evaluate the relationship of baseline retinal-vessel calibers to the risk of glaucoma progression.Over a mean follow-up period of 34.36 ± 5.88 months, 69 NTG eyes (17.69%) developed progressive RNFL thinning and 22 eyes (5.64%) developed VF deterioration. In the multivariable Cox regression analysis adjusting for age, gender, IOP, MOPP, SBP, AL, SAP MD and RNFL thickness, narrower baseline CRAE (hazard ratio (HR) per SD decrease (95% confidence interval), 1.36 (1.01-1.82)) and CRVE (1.35 (1.01-1.80)) were associated with progressive RNFL thinning, and narrower baseline CRAE (1.98 (1.17-3.35)) was associated with VF deterioration.In this study, each SD decrease in the baseline CRAE or CRVE was associated with more than 30% increase in the risk of progressive RNFL thinning, and more than 90% increase in the risk of VF deterioration during the follow-up period. Baseline attenuation of retinal vasculature in NTG eyes was associated with subsequent glaucoma progression. High throughput DL-based retinal vasculature analysis demonstrated its clinical utility for NTG risk assessment.Copyright © 2022. Published by Elsevier Inc.