To investigate the ocular neovascularization (ONV) rate in eyes with a branch retinal artery occlusion (BRAO) or a central retinal artery occlusion (CRAO), and to study factors that may influence the ONV rate secondary to CRAO.This was a retrospective case series of consecutive patients (286 total eyes: 83 CRAOs and 203 BRAOs) who were diagnosed with a retinal artery occlusion from 1998 to 2013 at the Retina Consultants of Alabama and University of Alabama at Birmingham, Birmingham, AL, USA. Generalized estimating equations were used to evaluate the association between hypothesized risk factors and ONV development.Twelve (14.5%) of the 83 eyes with a CRAO developed ONV. Eleven of 12 eyes (91.7%) had iris neovascularization, ten of 12 eyes (83.3%) had neovascular glaucoma, and two of 12 eyes (16.7%) had neovascularization of the optic disc. The average time for ONV development secondary to CRAO was 30.7 days, ranging from the date of presentation to 137 days. Only two (<1.0%) of the 203 eyes with a BRAO developed iris neovascularization. Diabetes mellitus type 2 was a risk factor for ONV development following a CRAO with an adjusted odds ratio of 5.2 (95% confidence interval: 1.4-19.8) (P=0.02).ONV is an important complication of CRAO and is a less-frequent complication of BRAO. Patients with a CRAO, especially those with diabetes mellitus type 2, should be closely monitored for the first 6 months for ONV.