A method for pre-filling a hemodialysis apparatus includes providing a hemodialysis apparatus comprising a pre-filling liquid source which supplies a pre-filling liquid, a dialyzer, a dialysate side, a blood side. The dialysate side comprises a dialysate chamber, a dialysate pump to pump the pre-filling liquid to the dialysate chamber, and a waste pump to pump the pre-filling liquid away from the dialysate chamber. The blood side comprises an arterial line, a blood pump, a blood chamber of the dialyzer, and a venous line. A pressure sensor is arranged on the dialysate side or on the blood side. The arterial line and the venous line are pre-filled with the pre-filling liquid via the dialysate pump. A blood-side fluid pressure is continuously determined via the pressure sensor during the pre-filling. The pre-filling is stopped when the blood-side fluid pressure determined by the pressure sensor exceeds or falls below a defined limit pressure.
