The invention relates to the field of a semiconductor, and discloses an LED epitaxial structure. The LED epitaxial structure comprises a substrate, a nucleating layer, a non-doped GaN layer, an n type GaN layer and a porous SiN<x> layer on the n type GaN layer, and also comprises an n type GaN hexagonal-pyramid array formed in the holes of the porous SiN<x> layer, and quantum dots on the peak of the hexagonal pyramid, quantum lines on the six ridges and a multi-quantum-well layer on six semi-polar (10-11) crystal surfaces, and a p type GaN filling layer at the tail part; and the GaN hexagonal pyramid and the quantum dots/lines/well layer at different positions thereon form the three-dimensional core-shell structure. The structure is large in light emitting area and high in light extracting efficiency; in addition, due to influences of different In contents and polarization effects and other factors, the light emitting wavelengths of the quantum dots/lines/well structures are also different; through reasonable control, white light emission can be realized; in the preparation method of the GaN hexagonal pyramid array, substrate patterning is not needed, so that the technological process is simple; and meanwhile, the grown GaN crystals are high in quality, so that the luminous efficiency of the LED can be improved effectively.