A light-emitting element comprises a substrate; a light-emitting semiconductor stack on the substrate, the light-emitting semiconductor stack comprising a first semiconductor layer, a second semiconductor layer on the first semiconductor layer, and a light-emitting layer between the first semiconductor layer and the second semiconductor layer; a first electrode on the first semiconductor layer; a reflective layer formed on the light-emitting semiconductor stack; a protection layer formed on the light-emitting semiconductor stack; and a conductive contact layer formed on the light-emitting semiconductor stack, wherein each layer above the substrate comprises a side surface inclined to a top surface of the substrate.