A hemodialysis apparatus that carries out hemodialysis treatment by controlling dialysis conditions, wherein the hemodialysis treatment is carried out under dialysis conditions determined by defining the course of said chronological target blood indication level as a target control line, measuring the blood indication level at each measurement point (controlling point) in said chronological course, calculating the dialysis conditions with the use of said measured blood indication level and the target blood indication level at the next measurement point (controlling point) of said measurement point (controlling point) in the hemodialysis apparatus carrying out hemodialysis treatment by controlling dialysis conditions with the use of blood volume (BV level) or blood volume change as an indication level (hereinafter also referred to as blood indication level), to attain the target blood indication level at the next measurement point (controlling point). This apparatus has a simple control mechanism and has little risk of misoperation or out-of-control. An operator can easily handle it and the control can be quickly and precisely carried out. Therefore, the blood volume transits appropriately during hemodialysis, which is an excellent effect.