Optical coherence tomography (OCT) is a widely used technique for the measurement of retinal nerve fiber layer (RNFL) thickness. It emits a light from the light source to the retina or reference mirror and measures RNFL thickness by detecting the different reflectivities of retinal structures.1 Therefore, any media opacity in the cornea, lens, or vitreous body can affect OCT measurement. However, little is known about the effect of vitreous opacity on RNFL thickness measurement. Vitreous opacity associated with age-related posterior vitreous detachment is a commonly found abnormality.2,3 In aged eyes with posterior vitreous detachment, a vitreous opacity can float around the optic disc and can affect peripapillary RNFL measurement. We report 3 cases of peripapillary vitreous opacities with or without RNFL thickness change in eyes with ocular hypertension or glaucoma.