Purpose: To assess the association between the choroidal vascularity index (CVI) and prelaminar tissue thickness (PTT) in healthy and glaucomatous eyes. Methods: The study included 86 eyes with perimetric glaucoma (PG), 86 with pre‐perimetric glaucoma (PPG), and 43 agematched healthy eyes. Total choroidal area (TCA) and CVI were measured by image binarization of spectral‐domain optical coherence tomography (SD‐OCT) 3.5 mm from the center of Bruch’s membrane opening. The CVI was the percentage of choroidal vasculature to choroidal tissue. The association between CVI and PTT measured on a center‐horizontal scan of enhanced depth imaging SD‐OCT was assessed. Results: The CVI was lowest in PG (61.67% ± 4.11%), followed by PPG (63.36% ± 3.54%), and healthy (64.84% ± 3.13%) eyes (p < 0.001). PG (102.05 ± 44.01 μm) had a significantly thinner PTT than PPG (106.16 ± 38.03 μm) and the healthy (154.98 ± 79.46 μm) eyes (p < 0.001). In a multivariate regression analysis, CVI was associated with PTT and TCA in all subjects, including healthy and glaucomatous eyes (p < 0.05). Conclusions The CVI and PTT had significantly lower values in glaucomatous eyes than in healthy eyes, and the two parameters were positively associated in all subjects, including healthy and glaucomatous eyes.