This　paper　is　devoted　to　the　rigorous　justification　of　the　quasi-neutral　limit　of　bipolar　transient　drift-diffusion　models　for　semiconductors　with　p-n　junctions　in　the　multidimensional　space.　The　general　initial　data　and　smooth　sign-changing　doping　profiles　with　good　boundary　conditions　are　considered.　The　limit　is　performed　rigorously　by　using　multiple　scaling　asymptotic　analysis,　in　which　one　main　point　is　the　construction　of　a　more　accurate　approximate　solution　involving　the　effect　of　initial　layer.　The　uniform　estimates　with　respect　to　the　scaled　Debye　length　are　obtained　through　the　elaborate　energy　method　and　the　relative　entropy　functional　method.