Abstract: As the fitting value of Michaelis-Menten pharmacokinetic parameters K_m and V_m of accurate linearre gress (AIR) or improved Hanes-woolf method has some deviation, a optimizing method of K_m and V_m was used in this paper. The result of ALR or improved Hanes-Woolf method was taken as the primary value of parameters (V_m and K_m). The method combined Runge-kutta alorithm with program solution in Excel software (RK-PS was used to minimum weighting residual square sum [$\sum$(c-c *) 2/c] of concentration. The primary value of parameters was optimized. The RK-PS method was better than ALR method and improved Hanes-woolf method intwo examples.

Key words: pharmacokinetics, Runge-kutta algo-rithm, parameter, Excel software, program solution