Disclosed is a light emitting device including a substrate, a light emitting structure arranged on the substrate, the light emitting structure including a first semiconductor layer, a second semiconductor layer and an active layer arranged between the first semiconductor layer and the second semiconductor layer, a first electrode electrically connected to the first semiconductor layer, and a second electrode electrically connected to the second semiconductor layer, wherein the light emitting structure has a top surface including a first side and a second side which face each other, and a third side and a fourth side which face each other.