The films of polymeric composites based on non-photoconducting polyvinyl alcohol and polystyrene doped by various concentration of xanthene and triarylmethane type dyes have been prepared. Their photophysical, electrical, and spectral properties have been investigated. It was shown, that all studied composite films exhibit photovoltaic properties and anomalous negative photoconductivity effect. The diffusion nature of observed photovoltaic effect was established. The features of photovoltaic effect and photoconductivity, as well as the possible negative photoconductivity mechanism are discussed.