A GaN-based light-emitting device and the fabricating method for the same are described. The light-emitting device is a light-emitting body with a light extraction layer thereon. The light-emitting body has some GaN-based layers and is capable of emitting a light when energy is applied. The light extraction layer is a double layered structure having a current spreading layer and a micro-structure layer, or a single layered structure without the current spreading layer. The micro-structure layer is a TiN layer with a nano-net structure obtained by nitridation of a Ti layer or a Pt layer with metal clusters thereon obtained by annealing of a Pt layer.