Clinically there is no such thing as the best blood type, because blood types currently mainly take ABO typing and RH typing, that is, the common A blood type, B blood type, O blood type and AB blood type, and then RH negative and positive typing. Because of the specific typing of blood groups, there are many other classifications, but the above two typing methods are the main ones that guide the clinical significance. The blood type depends mainly on the genes, on the blood type category of the parents, and the corresponding pairing according to Mendel’s law of inheritance, which determines the blood type of the next generation. Some studies have shown the possibility of some correlation between certain diseases and a certain type of blood type, but there is a lack of evidence from evidence-based medicine and no clinical experience. Therefore, clinically there is no such thing as which blood type is good and which blood type is bad in current medicine.