We　investigate　the　time-asymptotic　stability　of　planar　rarefaction　wave　for　the　3D　bipolar　Vlasov　Poisson　Boltzmann　(VPB)　system,　based　on　the　micro　macro　decompositions　introduced　in　[T.　P.　Liu　and　S.　H.　Yu,　Boltzmann　equation:　Micro-macro　decompositions　and　positivity　of　shock　profiles,　Comm.　Math.　Phys.　246　(2004)　133-179;　Energy　method　for　the　Boltzmann　equation,　Physica　D　188　(2004)　178-192]　and　our　new　observations　on　the　underlying　wave　structures　of　the　equation　to　overcome　the　difficulties　due　to　the　wave　propagation　along　the　transverse　directions　and　its　interactions　with　the　planar　rarefaction　wave.　Note　that　this　is　the　first　stability　result　of　basic　wave　patterns　for　bipolar　VPB　system　in　three　dimensions.