PROBLEM TO BE SOLVED: To provide a blood component separation apparatus and blood component separation method which prevent coagulation of a predetermined blood component (e.g., platelet) in a storage bag for storing the predetermined blood component.SOLUTION: A blood component separation apparatus according to one aspect of the present invention comprises: a centrifugal separator for separating a predetermined blood component from blood and a storage bag for storing the centrifugally separated predetermined blood component, where the storage bag is a bag for directly storing the predetermined blood component which has flowed out from the centrifugal separator, the storage bag performing a step of injecting a predetermined amount of a preservation liquid thereinto at any timing before storing the predetermined blood component therein, and the storage bag not containing the preservation liquid at all before performing the step.SELECTED DRAWING: Figure 1
