Abstract. The dose calculation parameters of 103Pd radioactive seed need to be determined strictly before clinical application for tumor implanted treatment. The radial dose function and the anisotropy factor are data analyzed and nonlinear fitted based on the value of dose parameters in American Association of Physicists in Medicine (AAPM) TG-43 and TG-43U1 by Cftool and SFTool toolbox in Matlab. Result was selected according to the optimum principle of fitting accuracy that is the coefficient of determination is close to 1 and gets the minimum value of the sum of square of deviations in fitting process. The calculation of the radial dose function and the anisotropy factor result are obtained in an ideal situation, and then the dose calculation of 103Pd radioactive seed is determined. The calculation of 103Pd radioactive seed provides a theoretical basis for 103Pd implanted treatment of tumor in clinical.