A hemodialysis apparatus includes a dialyzer, a quantitative vessel including a displaceable partition wall which partitions the inside of the quantitative vessel into a first chamber and a second chamber, a storage vessel which stores a dialysate, a dialysate exchange circuit which supplies the dialysate to the first chamber, and discharges a waste dialysate in the second chamber to the outside by the consequent displacement of the partition wall to the second chamber side, a dialysate supply circuit which supplies the dialysate in the first chamber to the dialyzer, and discharges the waste dialysate from the dialyzer to the second chamber by the displacement of the partition wall to the first chamber side, and a dialysate storage circuit which supplies the dialysate in the first chamber to the storage vessel by the displacement of the partition wall to the first chamber side.