The single-phase polycrystalline Sm-filled skutterudites SmyFexCo4-xSb12 were investigated by Rietveld refinement and Raman scattering spectral analysis. The results of Rietveld refinement clarify that the SmyFexCo4-xSb12 compound has a filled skutterudite structure. The thermal parameter of Sm is larger than that of Sb, Fe and Co, and the Sb-Sb bond length of SmyFexCo4-xSb12 is longer than that of unfilled skutterudites. The results of Raman scattering study show a shift and broadening of the Sb4 ring breathing modes. These results indicate that Sm atoms fill the Sb-icosahedron voids of the skutterudites and rattle in them.