A hemodialysis apparatus that carries out hemodialysis treatment by measuring or calculating the blood volume or its volume change as a blood indication level, and by controlling dialysis conditions according to said target blood indication level, wherein the chronological course of said blood indication level is defined as a target control line, and the primary blood volume (BV.sub.0) can be calculated as blood indication level. In the former part of the dialysis operation, the water removal is controlled so that the circulating blood volume in the body approach to the standard blood volume (BV st) with the use of said target control line. After the water removal of the former part of the dialysis operation, when the circulating blood volume in the body attains the standard blood volume (BV st), the latter part of the dialysis operation is started. In said latter part of the dialysis operation, the water removal operation is performed by substantively maintaining said standard blood volume (BV st).
This application is a divisional application of application Ser. No. 10/484,850, filed Apr. 12, 2004 now U.S. Pat. No. 7,241,378, which is a national stage application of International Application Number PCT/JP02/07597 filed Jul. 26,2002, both of which applications are incorporated herewith.
