Resonance Raman spectra and its dependence on the excitation photon energy of partially isomer ized and all trans-polyacetylene prepared by rare-earth catalyst were compared with that of polyacetylene prepared by Shirakawa's catalyst. Resonance Raman spectra have been reported firstly for soluble polyacetylene prepared by rare-earth catalyst. The observed results seem to support the consideration of that the observed Raman anomaly for trans-polyacetylene is originated from dispersion of conjugation length in polyacetylene chain.