To provide a blood purification apparatus in which the fact that neither an arterial puncture needle nor a venous puncture needle is stuck in the patient can be checked automatically when it is attempted to activate a blood pump in an unconnected step. A blood purification apparatus includes a blood circuit 1 capable of extracorporeally circulating blood of a patient, a dialyzer 2 capable of purifying the blood flowing through the blood circuit 1, a blood pump 3 provided to an arterial blood circuit 1a and being capable of delivering liquid when activated, and a control device 10 that executes a connected step in which the blood pump 3 is activated with an arterial puncture needle a and a venous puncture needle b being stuck in the patient and an unconnected step in which the blood pump 3 is activated with neither the arterial puncture needle a nor the venous puncture needle b being stuck in the patient. The control device 10 is capable of executing, in the unconnected step, a checking step in which whether the arterial puncture needle a and/or the venous puncture needle b is not stuck in the patient is checked.
