The present invention discloses an epitaxial structure for semiconductor light-emitting device, comprising an electron injection region, a hole injection region, a multi-quantum well active region, a potential barrier layer for blocking carriers, and one or more band edge shaping layers. The doping type and/or doping concentration of said band edge shaping layers are different from those of the adjacent layers. It may trim the band edge shape of the semiconductor energy band through the local built-in electric field formed as a result of adjusting the doping type, doping concentration and/or layer thickness thereof, such that the carriers in the multi-quantum well active region are distributed uniformly, the overall Auger recombination is decreased, and the effective potential barrier height of the potential barrier layer for blocking carriers is increased to reduce the drain current formed by carriers overflowing out of the multi-quantum well active region, thereby improving internal quantum efficiency. The present invention further discloses a semiconductor light-emitting device that employs said epitaxial structure, which similarly achieves the effects of reduced Auger recombination and/or decreased drain current through the trimming of the band edge shape of the energy band structure by the local built-in electric field, thereby improving internal quantum efficiency of the device.