Abstract: A light-emitting diode includes from bottom to up: a substrate, a first-conductive type semiconductor layer, a super lattice, a multi-quantum well layer and a second-conductive type semiconductor layer. At least one layer of granular medium layer is inserted in the super lattice. The granular medium layer is used for forming V pits with different widths and depths in the super lattice. The multi-quantum well layer fills up the V pits and is over the top surface of the super lattice. The number of micro-particle generations, positions and densities can be adjusted by introducing granular medium layers and controlling the number of layers, position and growth conditions during super lattice growth process, to ensure V pits of different depths and densities. This can change hole injection effect, effectively improve hole injection efficiency and distribution uniformity in all quantum wells, thus improving LED light-emitting efficiency.