The retinal blood oxygen quantification method is a fast and non-invasive new retinal vascular imaging technology, which is used to reflect the metabolism of retinal blood oxygen and the micro-circulation of whole body by measuring, analyzing and quantifying the blood oxygen saturation of the main arteries and veins of the retina. The circulation state provides a reliable basis for medical diagnosis. Retinal blood oxygen saturation can be used as a biomarker for the diagnosis and evaluation of ophthalmologic and brain diseases such as diabetic retinopathy, central retinal vein occlusion, retinitis pigmentosa, glaucoma and Alzheimer's disease.