Abstract:The UV-radiation acting on “pathogen-plant” pathosystems effects the development of plant diseases, mainly includes the two aspects: the first one is the photobiological response of plant pathogens to UV-radiation on the spore germination, germ tube extension and hyphal development, different species of pathogens have different response mechanisms to UV-radiation; secondly, host plants can make responses to UV-radiation on modality, physiology and biochemistry, resulting in the changes of disease resistance. The researches confirm that medium and short wave of UV-radiation can control the spore germination, decrease the incidence of plant diseases; long wave of UV-radiation can induce the spore germination, increase the incidence of plant diseases. According to the factors of UV-radiation level, the degree of pathogen infection, and resistant varieties of plant, UV-radiation have different acting mechanisms to different pathosystems. The writer of this paper reviewed the influence of UV-radiation on plant diseases depending on the domestic and overseas researches in recent years.