In the present work, thin films of poly(methyl methacrylate)/lead oxide nanoparticles composites [PMMA/PbO(NPs)] were prepared using solution-cast method. The effect of PbO NPs with different concentrations in the range from 0.26 to 1.00 wt% on the transmittance spectra in the spectral region 400-700 nm was followed using spectrophotometer tool, CIE tristimulus values and color parameters. The changes in the optical parameters including: absorption coefficient, band tail width and band gap energies, extinction coefficient and color strength as well as refractive index and dispersion parameters were investigated. The data obtained indicated that the optical parameters were highly affected by changing PbO NPs concentration. The dispersion parameters were changed by incorporation of PbO. In conclusion, the obtained optical parameters of PMMA were found to be strongly affected its optical properties by addition of PbO nanoparticles.