Component transfusion is a method of physically or chemically separating, concentrating and purifying the cellular components, plasma and plasma protein components of blood and supplementing them with whatever components are missing according to the patient’s needs. Component transfusion was first introduced by Gibson in 1959 and was first used clinically in the U.S. Since the 1960s, it has been rapidly carried out in some developed countries. By the early 1980s, component transfusions had reached 60%-80% of total blood collection abroad. Currently, component transfusion has become one of the symbols to measure the development of blood transfusion in a country. In China, component transfusion started a little later and is still limited to blood centers and large hospitals in major cities. Beijing, Shanghai, Tianjin, Chengdu and other places are developing faster. The advantages of component blood transfusion are: 1) high purity, good efficacy; 2) safe transfusion, few side effects; 3) saving blood, multiple use of one blood. The advantages of blood transfusion include: 1) good purity and efficacy; 2) safe transfusion with few side effects; 3) economical use of blood and multiple uses of blood, fully reflecting the comprehensive utilization of blood sources; 4) easy preservation and transportation; 5) cheap price and increased social and economic benefits. Component blood transfusion is an important revolution in the history of blood transfusion, which has given a new look to blood transfusion from theory to practice and is of great significance in promoting the development of medicine.