The present invention is a blood purification device provided with: a blood circuit that has an artery-side blood circuit and a vein-side blood circuit and that performs extracorporeal circulation of the blood of a patient in a state where a blood purifier for purifying the blood of the patient is disposed between the artery-side blood circuit and the vein-side blood circuit； a dialysis liquid dispensing chamber that temporarily reserves a dialysis liquid in a dialysis liquid storage part supported by a support part； a replenishment liquid dispensing chamber that temporarily reserves a replenishment liquid in a replenishment liquid storage part supported by the support part； a first dialysis liquid introduction line for distributing, to the dialysis liquid dispensing chamber, a dialysis liquid stored in the dialysis liquid storage part； a replenishment liquid line for distributing, to the replenishment liquid dispensing chamber, the replenishment liquid stored in the replenishment liquid storage part. The blood purification device comprises: a dialysis liquid transfer pump that is provided to the first dialysis liquid introduction line and that transfers, to the dialysis liquid dispensing chamber, the dialysis liquid in the dialysis liquid storage part； a replenishment liquid transfer pump that is provided to the replenishment liquid line and that transfers, to the replenishment liquid dispensing chamber, the replenishment liquid in the replenishment liquid storage part； and a control unit that controls the dialysis liquid transfer pump and the replenishment liquid transfer pump.La présente invention concerne un dispositif d'épuration de sang comportant : un circuit sanguin qui a un circuit sanguin côté artère et un circuit sanguin côté veine et qui effectue une circulation extracorporelle du sang d'un patient dans un état dans lequel un épurateur de sang pour épurer le sang du patient est disposé entre le circuit sanguin côté artère et le circuit sanguin côté veine
