A blood component separation device for separating a plurality of blood components from blood sampled from a blood donor, and collecting platelets, includes: a donor calculation unit that calculates a predicted platelet recovery rate from a hematocrit value of the blood and a platelet concentration of the blood, and calculates a recommended processing amount of the blood recommended for collecting a target number of units of platelets on the basis of the calculated predicted platelet recovery rate, wherein the operating unit sets the predicted platelet recovery rate calculated from any the hematocrit value and any the platelet concentration to be smaller by a predetermined value α when the blood donor is female than that when the blood donor is male.