Though a lot of stone bridges in Kumamoto prefecture were administered as the variable cultural heritage, it was found here and there for stone bridges with damaged stones, gaps and falls. In order to propose the soundness evaluation method and the simply inspection method for these damaged structures, the development of the static analytical method of stone arch bridge taking into account the stone damage, gaps and falls are investigated theoretically and experimentally. The coefficient of longitudinal and shear spring between two tones was obtained from compression and shear tests and these springs was introduced into RBSM analysis. The mechanical behavior of stone arch bridges were carried out by this program and it was shown the numerical results can simulate fairly well the results of a miniature stone arch model test.