Keratitis, as the name implies, is an inflammation of the corneal tissue of the eye and can be divided into infectious and non-infectious keratitis depending on the presence or absence of infectious factors. The main manifestation of inflammation is redness, swelling, heat and pain, so the main symptoms of inflammation of the cornea are redness, eye pain, photophobia and discharge, because the cornea is an important refractive interstitium of the eye and lesions that occur here can lead to vision loss. Infectious keratitis and non-infectious keratitis can be classified according to the presence or absence of infectious factors. Infectious keratitis is usually caused by a combination of corneal epithelial cell damage, shedding or a decrease in body resistance, and its causes are bacterial and fungal infections most commonly. Patients with viral keratitis often have a history of recurrent disease, usually triggered by a cold, with aqueous discharge and non-significant ocular pain; in addition, there are also echinocococcosis infections, often due to wearing soft corneal contact lenses, unhygienic care of contact lenses or wearing corneal contact lenses for swimming or bathing, etc. These infections have intense pupillary redness and photophobia. Non-infectious keratitis is commonly caused by connective tissue diseases and autoimmune diseases without the presence of infectious factors. These types of keratitis can be effectively identified based on patient symptoms, medical history, slit lamp examination for lesion morphology, scraping of corneal lesions or corneal confocal microscopy, with emphasis on identifying the cause. The basic principle of treating keratitis is to take all effective measures to quickly control the infection, strive for early cure, and reduce the sequelae of keratitis (such as vision loss) to a minimum; keratoconus related to systemic diseases should be actively treated in addition to ophthalmic treatment for the primary disease. In summary, keratitis is an inflammation located in the corneal part, which can be divided into infectious and non-infectious. Once the symptoms of keratitis appear, you should seek medical attention and early treatment to reduce the impact on vision.