Abstract: C<SUB<60</SUB<-PMMA composite films on Si（100） substrate were prepared by the sol-gel method, and its IR spectra was studied. It was found that near the C<SUB<60</SUB< IR characteristic peaks (1 182 cm<sup<-1</sup< and 1 428 cm<sup<-1</sup<), there were red-shift and extension relative to IR absorption spectra in PMMA. Theoretically, we obtained C<SUB<60</SUB< and C<SUB<60</SUB< with different charges IR spectra. Investigations concluded that the reason why composite films IR spectra were observed with red-shift and extension was the occurance charge-transfers between C<SUB<60</SUB< and PMMA inducing pristine C<SUB<60</SUB< IR absorption spectra red-shift.