The main symptoms of keratitis are eye redness and eye pain, foreign body sensation, photophobia and tearing, discharge, and vision loss, and different treatments should be chosen depending on the cause. Corneal inflammation is not only characterized by eye irritation: eye redness, eye pain, photophobia and tearing, but also by vision loss because the cornea is an important refractive interstitial space in the eye and lesions that occur there, especially those located in the central cornea, can lead to vision loss. Keratitis can be divided into infectious keratitis and non-infectious keratitis based on the presence or absence of infectious factors. Infectious keratitis is commonly bacterial, fungal, and viral, and is usually caused by a combination of damage to the corneal epithelium, shedding, or a decrease in body resistance. Generally speaking, the symptoms are more severe and more acute for bacterial infections, while fungal infections stimulate mild symptoms and have a slow progression. Bacterial infections are common with Staphylococcus epidermidis infections, and antibiotic eye drops should be ordered frequently to control the inflammation. Patients with viral keratitis often have a history of recurrent disease, usually triggered by a cold, and can be treated with topical or systemic antiviral drugs such as acyclovir and ganciclovir. Non-infectious keratitis is commonly caused by connective tissue diseases and autoimmune diseases, without the presence of infectious factors, and should be treated first with systemic diseases and symptomatic treatment of ocular symptoms. In summary, the main symptom of keratitis is eye irritation accompanied by vision loss. Infectious keratitis should be treated with different drugs depending on the infectious factors, while non-infectious keratitis should be treated for the primary disease and symptomatic treatment of the eye.