Background: To explore microvascular changes in the optic disc (OD) of eyes with non-acute non-arteritic anterior ischemic optic neuropathy (NAION) using optical coherence tomography angiography (OCTA). Materials and Methods: This cross-sectional study enrolled patients with NAION for a duration exceeding 3 months along with healthy volunteers. Vascular density (VD) measurements for OD were obtained across the entire area, inside the disc peripapillary, and in the superior and inferior hemi-regions using OCTA on a 4.5 mm scan. Results: The mean age of the 41 NAION patients and 47 volunteers in the healthy group was 64.8±7.9 years and 62.9±7.5 years, respectively. No significant differences were observed in the sex and age distribution between the NAION patients and the healthy group. The mean VD of the optic nerve in the whole image for NAION patient eyes, fellow eyes, and the healthy group were 47.4±2.1, 50.0±2.3, and 49.6±2.0, respectively. Notably, the entire image VD in the NAION group was significantly lower than that in the other groups (p=0.001). Peripapillary and inferior VD in eyes with NAION were significantly lower than those in the other groups. However, no significant differences were observed in the inside disc and superior hemi VD between the patient and fellow eyes of NAION patients and the healthy group (p>0.179, p>0.829, respectively). Conclusion: This study demonstrated a significant reduction in entire image, peripapillary, and superior hemi VD of the OD in NAION patients during the chronic period.