Corneal dry spots are dry corneal spots formed due to the accumulation of corneal epithelium and are mainly seen in vitamin A deficiency disease. The disorder is a systemic nutritional disorder with ocular manifestations of vitamin A deficiency. The disease requires attention to the following differential diagnosis. (1) Differentiate from corneal conjunctival dryness (1) The surface of the conjunctiva is dry, dull and shapeless, easy to form folds, even as thick as skin, the conjunctival blood vessels are blue, the cornea is dry and cloudy, and the perception is dull. (2) Self-perceived dryness and burning of the eyes, and severe loss of vision. (3) Common in adults. (2) Other causes of night blindness such as retinitis pigmentosa, must be excluded, secondary infection can worsen corneal changes, trial of vitamin A in therapeutic doses helps to diagnose.