[en] We used the Monte Carlo method to evaluate s-value parameter for prediction of Sn-117m radio-pharmaceuticals production compared with I-131. In this study, we developed a customizable digital mouse phantom, because principal therapeutic applications of Sn-117m and I-131 are leukemia, lymphomas, solid tumor and metastatic bone pain. These applications are needed S-values of blood, tumor and bone for radiopharmaceuticals research. The results of this study, lower S-values of Sn-117m compared with I-131, can support to estimate Sn-117m radiopharmaceuticals production yield. It can further be applied to evaluate pharmacokinetics and pharmacodynamics research with dose calculation. In addition, the results can be used to determine proper administrative injection dose for radiopharmaceuticals.