We report on the spectroscopic ellipsometry (SE) characterization and modeling of the light and environmental induced degradation of Poly(p-phenylenevinylene) (PPV) prepared by xanthate precursor route. We find a decrease in the refractive index as well as absorption coefficients after exposure to light in air ambient. Further, a decrease in film density and increase in film thickness is also observed on light exposure in air. On the other hand, optical constants are not affected by light exposure in vacuum.