Hemosporidiosis is a common disease in dairy cows. The disease is mainly caused by the infection of four parasites：Babesia bovis,Babesia bovis,Taylor sphaerocephalus and Pseudomonas. Sick cows are mainly manifested by symptoms such as increased body temperature,jaundice,decreased production performance and anemia,which are more harmful to the dairy farming industry. This article mainly summarized the pathogen,clinical symptoms,diagnosis and treatment of hemosporidiosis in dairy cows,in order to strengthen the feeding and management,regular sterilizion of dairy farms,reduce the occurrence of this disease and economic losses,provide a theoretical basis for dairy healthy breeding.