A nitride-based semiconductor LED which is flip-chip bonded on a lead pattern of a sub-mount through a bump ball comprises a substrate; a light-emitting structure formed on the substrate; an electrode formed on the light-emitting structure; a protective film formed on the resulting structure having the electrode formed therein, the protective film exposing the electrode surface corresponding to a portion which is connected to the lead pattern of the sub-mount through a bump ball; and a grid-shape buffer film formed on the electrode surface exposed through the protective film.