The present invention provides a light emitting diode (LED) element which comprises a substrate, a buffer layer, a plurality of nano-spheres and a light emitting structure. The substrate comprises a plurality of grooves arranged at intervals on a surface of the substrate. The buffer layer is disposed on the surface of the substrate where the grooves being formed, wherein the grooves are disposed between the substrate and the buffer layer. The nano-spheres are received in the grooves, so each groove is provided with at least a nano-sphere. The light emitting structure is disposed on the buffer layer.