This paper discusses a new quantitative evaluation of the removal dynamics in the artificial kidney system. New therapeutic parameters (KC/V and CL/V) were introduced into the evaluation. By means of these parameters, which can be determined by simulation analysis, concentration-time profiles of each patient could be drawn during dialysis and off-dialysis periods. The newly defined concept of "CSMAX", which means a maximum solute concentration in stable periods, is presented as the characterization parameter in long-term treatment.