A light emitting device includes a conductive support member, a first conductive layer on the conductive support member, a second conductive layer, a first semiconductor layer on the second conductive layer, a second semiconductor layer and an active layer between the first semiconductor layer and the second conductive layer, and an insulation layer disposed between the first conductive layer and the second conductive layer. The first conductive layer includes a first expansion part penetrating the second conductive layer, the second semiconductor layer and the active layer, and a second expansion part extending from the first expansion part and disposed in the first semiconductor layer. The insulation layer is on a lateral surface of the first expansion part. At least a portion of a lateral surface of the second expansion part contacts the first semiconductor layer, and the insulation layer is between the first semiconductor layer and the second expansion part.