The invention relates to a method and a device for separating blood using a centrifuge in order to obtain different blood fractions. The aim of the invention is to eliminate the risk of contamination during the supply of blood and the removal of blood fractions. To achieve this, the separation container is filled with blood via a feed connection that can be aseptically connected to the container, the relevant blood fraction is removed from the separation container via a removal connection that can be aseptically connected to the container and both the feed device and the removal device form a respective closed system during the sterile connection to the separation container. The separation container (4) has at least one feed connection (5, 6) that can be aseptically connected to the container and at least one removal connection (7) that can be aseptically connected to the container, to which hermetically sealed feed and removal devices (8, 9, 10) can be aseptically attached in a sterile manner.
