Abstract: Based on the flow field solution of the three-porous-medium model for tumor microcirculation, the diffusion-convection equations are solved with varions initial and boundary conditions using finite element method.The concentration profile of two therapeutic agents immunoglobulin G(lgG) and its antigen-binding fragment (Fab) in blood,lymph and intersitial flaid are obtained for normal-tissue-surrounded tumor.The effect of tumor microvasculature, lymph function,drug injection mode,the molecular weight and binding kinetics of the drug on the distribution in tumors are considered.