Currently, uveitis is generally considered to be a general term for inflammation in the eye, which includes inflammation of the uvea, retina, retinal vessels and vitreous humor. It occurs in young adults, often in combination with systemic autoimmune disease, is recurrent, causes serious complications, and is a common type of blinding ophthalmic disease. There are many ways to classify uveitis, but it is usually classified by etiology, site of inflammation, nature of inflammation, pathological changes, and urgency of onset. Classification by etiology: tuberculous uveitis, syphilitic uveitis, toxoplasmic uveitis, leptospirosis uveitis, histoplasmosis uveitis, viral uveitis, etc. Classification by inflammation site: such as anterior uveitis (iritis, uveitis), posterior uveitis (chorioretinitis), peripheral uveitis (also known as intermediate uveitis or flatulitis), and total uveitis. Classification by nature of inflammation: divided into purulent uveitis and non-purulent uveitis. Classification by pathological changes: granulomatous uveitis and non-granulomatous uveitis. Granulomatous is mostly caused by tuberculosis, syphilis, leprosy, Toxoplasma gondii and leptospirosis, and generally has a slow course, mild inflammation, and commonly has iris nodules; the pathological changes are mainly mononuclear phagocytes, lymphocytes, plasma cells, epithelioid cells and macrophages forming nodules. Non-granulomatous is mainly caused by immune response, mostly exudative inflammation, with an acute course and heavy inflammation; infiltrative infiltration by lymphocytes and plasma cells only, without nodule formation. It is classified according to the urgency of onset: acute, subacute, chronic and old. For example, acute iridocyclitis, chronic iridocyclitis, old chorioretinitis, etc.