PROBLEM TO BE SOLVED: To provide an apparatus for collecting a blood component, which beforehand prevents or moderately suppresses the occurrence of internal hemorrhage in a blood return process.SOLUTION: The apparatus 10 for collecting a blood component has a controlling unit 26 for driving a blood pump 28 that feeds the blood component to a blood return line. When the blood pump 28 is rotated to thereby start blood return, the controlling unit 26 performs pressure determination processing for slowing down or stopping the blood pump 28 when pressure Pd to be obtained from a pressure sensor 38 exceeds a control threshold 502 or a stop threshold 501 that has been set corresponding to the cumulative rotational number, cumulative blood feeding quantity, or blood return elapsed time of the blood pump 28 or when the inclination of the pressure Pd exceeds a prescribed inclination PL2.COPYRIGHT: (C)2012,JPO&INPIT【課題】返血工程において、内出血の発生を事前に予防し、若しくは適度に抑えることのできる血液成分採取装置を提供する。【解決手段】血液成分採取装置10において、返血ラインに血液成分を送り出す血液ポンプ28を駆動する制御部26は、血液ポンプ28を回転させて返血を開始した際に、圧力センサ38から得られる圧力Pdが血液ポンプ28の累積回転数、累積送液量又は返血経過時間に対応して設定された制限用閾値502又は停止用閾値501を超えるとき、又は前記圧力Pdの傾斜が所定傾斜PL2を超えるときに、血液ポンプ28を減速又は停止させる圧力判断処理を行う。【選択図】図7