A light-emitting diode (LED) device, includes a substrate, having a first and a second surfaces, a first bonding layer, disposed on the first surface, a first epitaxial structure, having a third and a fourth surfaces and comprising a first and a second groove, wherein the first epitaxial structure comprises a second electrical type semiconductor layer, an active layer and a first electrical type semiconductor layer sequentially stacked on the first bonding layer, and the first groove extends from the fourth surface to the first electrical type semiconductor layer via the active layer, the second groove extends from the fourth surface to the third surface, a first electrical type conductive branch, a first electrical type electrode layer, an insulating layer, filled in the first and the second grooves, and a second electrical type electrode layer, electrically connected to the second electrical type semiconductor layer.