Abstract- In this paper the generation of an entangled photon pair in polarization is described via the biexciton-exciton cascade of a quantum dot located in the proximity of a metallic nano-sphere. In order to make the intermediate states degenerate, we have invoked from dressed state approach. Within the strong coupling regime, an exciton and a principal plasmon mode of a given polarization are coupled and this interaction gives rise to two similarly polarized polariton states. In the generated photon pairs, either both photons are spontaneously emitted from the dot, or one photon is emitted from the biexiton spontaneously and the other is emitted via the scattering of principal plasmon mode to other plasmon mode of metal nano-sphere. In the strong coupling regime, the generated photon pairs can be maximally entangled