A light-emitting diode includes a support substrate, a semiconductor stack disposed on the support substrate, the semiconductor stack including a p-type compound semiconductor layer, an active layer and a n-type semiconductor layer, a reflective metal layer disposed between the support substrate and the semiconductor stack, the reflective metal layer being in ohmic contact with the p-type compound semiconductor layer of the semiconductor stack and having a groove exposing a portion of the semiconductor stack, a first electrode pad contacting the n-type compound semiconductor layer of the semiconductor stack, an electrode extension connected to the first electrode pad, the electrode extension disposed directly over the groove along a line perpendicular to the support substrate, an upper insulation layer disposed between the first electrode pad and the semiconductor stack. The electrode extension includes an Ni layer contacting the n-type compound semiconductor layer, and two Au layers disposed on the Ni layer.