A hemodialysis apparatus includes a dialysis device, a detecting device, an evaluation device and a memory device. The dialysis device dialyzes and ultrafiltrates blood of a patient according to an ultrafiltration volume based on an estimated dry weight while performing hemodialysis treatment on the blood circulating extracorporeally. The detecting device obtains time series data by measuring a parameter related to concentration of the blood circulating extracorporeally at a plurality of points in time series in a process of the hemodialysis treatment by the dialysis device. The evaluation device evaluates appropriateness of the hemodialysis treatment by evaluating whether the estimated dry weight approximates to a dry weight after the hemodialysis treatment by the dialysis device. The memory device stores a plurality of time series data when the hemodialysis treatment is evaluated to be appropriate by the evaluation device.