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Raman scattering of filled skutterudite compounds RT4X12 (R=La, Ce, Pr, Nd, Sm and Yb, T=Fe, Ru and Os, X=P and Sb) have been measured. All first order Raman active phonons are observed and are assigned as the pnicogen vibrations. In addition, at the low energy region, the 2nd order phonons due to the local vibrations of the rare-earth ions are also observed for RRu4P12 and ROs4Sb12. The appearance of the 2nd order phonon in Raman spectrum is caused by a large amplitude vibration of the rare-earth ion in large cage space. This rareearth vibration and pnicogen's one, which changes the R-X bond length, show the significant resonance scattering depending on the incident energy except for the semiconductive CeFe4P12. This result suggests the existance of the interaction between the R-X stretching-like vibration and conduction electron.

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