A medical bag hanger (92) hangs a plurality of bags (16) of a blood sampling line set (12). The medical bag hanger (92) includes a hanger main body (94) hangable on a centrifugal device (14); and a hook unit (96) which is provided in the hanger main body (94) and on which the plurality of bags (16) is hooked. The hanger main body (94) includes a base plate (98) provided with the hook unit (96). The plurality of bags (16) is arranged side by side on a surface of the base plate (98).