ABSTRACT
To introduce the origin, development and theoretical source of the bloodletting therapy overseas. The bloodletting therapy, which was based on Hippocrates's four fluid theories, had the therapeutical effect and therefor spread abroad. Many people not only thought this therapy was benefit, but also let out blood regularly. During the medieval Europ, the bloodletting therapy reached its top, which was caused by the part-time job of barber. It was questioned when spreading in the America. After that, as the development of the other medical method, the disadvantage was exposed. With several clinical mistherapies, it faded away from the stage of history. The recent research shows that the normative bloodletting therapy could treat some diseases.