We present an integral equation theory based on the polymer reference interaction site model (PRISM) formalism to describe a phase behavior of polymer containing colloidal dispersion. We focus on the thermodynamic stability of dispersed component, i.e., on the conditions of percolation and phase separation in this subsystem. Different phase diagrams for the colloid subsystem are constructed in the variables: volume fraction of the colloid component-temperature. We analyze the behavior of the spinodal line and the percolation threshold. It was shown that the spinodal lines do not exhibit a critical point. The additivity of a polymer induced and a direct attraction between the colloidal particles is examined.