An embodiment discloses a semiconductor device including a light emitting structure including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer; a first electrode electrically connected with the first conductive semiconductor layer; and a second electrode electrically connected with the second conductive semiconductor layer, and a semiconductor device package including the same. The second conductive semiconductor layer includes a first surface on which the second electrode is disposed. The second conductive semiconductor layer has a ratio of a second shortest distance W2, which is a distance from the first surface to a second point, to a first shortest distance W1, which is a distance from the first surface to a first point, (W2:W1) ranging from 1:1.25 to 1:100. The first point is a point at which the second conductive semiconductor layer has the same aluminum composition as a well layer of the active layer closest to the second conductive semiconductor layer. The second point is a point at which the second conductive semiconductor layer has the same dopant composition as the aluminum composition.