First we present a new micro-macro decomposition around the local Maxellian to the bipolar Vlasov-Poisson-Boltzmann equations.Then as an application of the decomposition,the time-asymptotic stability of the rarefaction wave is proved to the bipolar Vlasov-Poisson-Boltzmann equations.Note that this is the first result for the time-asymptotic stability of the non-constant states for the VPB equations as far as we know.