AbstractPurpose This study will investigate the optic nerve head (ONH) using optical coherence tomography (OCT) and analyze the correlations between neuroretinal rim and optic disc‐cup structure in order to apply the finding in glaucoma.Methods This cross‐sectional study enrolled 157 healthy subjects firstly and analyzed one randomly selected eye in each subject. The measurements for ONH parameters, including neuroretinal rim and optic disc‐cup structure (disc or cup areas and cup‐to‐disc ratios), were taken by a single experienced operator. The associations among neuroretinal rim and optic disc‐cup structure were determined. Independent parameter was further tested in 25 glaucomatous patients.Results In healthy subjects, average cup‐to‐disc area ratio estimated was 0.2827 ± 0.1134 (95% CI; range, 0.263 to 0.302); rim area (vertical cross section), vertical integrated rim area, horizontal integrated rim width, and rim area positively correlated with disc area (p<0.05); rim area (vertical cross section), average nerve width, and vertical integrated rim area negatively correlated with cup area (p<0.05); and rim area (vertical cross section), average nerve width, vertical integrated rim area, horizontal integrated rim width, and rim area negatively correlated with cup‐to‐disc ratios (p<0.05). In further stepwise regression analysis, average nerve width was not associated with optic disc‐cup structure measurements (p>0.05, F<4.000) in healthy subjects. In glaucomatous patients, average nerve width was positively correlated with the mean deviation (dB) in standard automated perimetry (p<0.001, r=0.709).Conclusion Average nerve width (the height of the nerve fiber bundle) is an independent rim parameter, and is helpful for the evaluation in glaucoma.