Keshan disease is a disease of unknown cause characterized by myocardial lesions, also known as endemic cardiomyopathy. It was first discovered in Keshan County, Heilongjiang Province in 1935, hence the name Keshan disease. In the past, the mortality rate of this disease was high. After the founding of New China, active prevention and treatment of this disease have significantly reduced the incidence and mortality of this disease. Some important progress has also been made in prevention, treatment methods and etiology research. At present, the annual incidence rate has dropped to below 0.07/100,000, and the type of disease has changed from acute and subacute to latent and chronic. A large number of epidemiological, pathological anatomy, clinical prevention and treatment, and laboratory research results show that this disease is an independent endemic cardiomyopathy.