The invention discloses an inverted mounting LED chip based on double-faced shrinkage pool substrate and component gradual change buffer layer, wherein the chip comprises a sapphire substrate distributed with 102-104 shrinkage pools at upper and lower surfaces, an AlxGa1-xN component gradual change buffer layer composed of an unit layer formed by k non-doping AlxGa1-xN epitaxial materials, a n-type GaN epitaxial layer, an InGaN / GaN multi-quantum well, a p-type GaN layer, a transparent ITO (indium tin oxide) conductive film, an inverted mounting welding electrode and a silicon substrate from upper to lower. The LED chip disclosed by the invention uses the shrinkage pool structure for improving the emergent probability of LED emergent lights, and increasing the heat radiation area and growth stress acting range of the substrate, so that the GaB epitaxial quality and the radiation composite luminous efficiency are improved; the buffer layer of the n-type GaN epitaxial layer is manufactured by the AlxGa1-xN with gradually reduced Al component, so that the light-emitting efficiency and the internal quantum efficiency of the LED are improved, and a relatively high light output power is obtained.