This review presents basic information on UV corneal crosslinking. The method is widely used in ophthalmology to treat various types of ectasia, which are characterized by progressive degenerative changes in the cornea, associated with its thinning , hazing and scarring, which leads to a significant reduction in visual acuity. Crosslinking is based on ultraviolet (UV) irradiation of the cornea wavelength 370 nm in the presence of riboflavin, leading to photochemical intracorneal interactions. As a result of crosslinking of collagen treatments, an increase of strength and mechanical properties of the cornea, stops the progression of the disease. The article displays the steps of the method development and the ways of its implementation are described especially occurring biomechanical, biochemical, morphological and ultrastructural changes, as well as the main areas of clinical application of riboflavin-UV-A-induced crosslinking of cornea.