A light emitting device comprising: a light emitting structure including a first conductivity type semiconductor layer, an active layer and a second conductivity type semiconductor layer; a passivation layer surrounding a side of the light emitting structure; a first electrode disposed on the first conductivity type semiconductor layer; a current blocking layer (CBL, 130) disposed under the second conductivity type semiconductor layer; an ohmic layer forming transparent electrode disposed under the second conductivity type semiconductor layer, the transparent electrode directly contacting the second conductivity type semiconductor layer and surrounding side surfaces and under surface of the CBL; a reflective electrode disposed under the second conductivity type semiconductor layer, the reflective electrode directly contacting the second conductivity type semiconductor layer, and surrounding side surfaces and under surface of the transparent electrode; a channel layer made of a metal disposed under the light emitting structure and surrounding side surfaces and under surface of the reflective electrode; and a support substrate connected to the channel layer through an adhesive layer, wherein the current blocking layer faces the first electrode, an upper surface of the current blocking layer is disposed on the same line as a lower surface of the second conductivity type semiconductor layer, the channel layer separates the passivation layer from the reflective electrode, the passivation layer directly contacts the channel ayer at the outer surface of the light emitting structure, and the channel layer directly contacts the reflective electrode. a light emitting structure including a first conductivity type semiconductor layer, an active layer and a second conductivity type semiconductor layer; a passivation layer surrounding a side of the light emitting structure; a first electrode disposed on the first conductivity type semiconductor layer; a current blocking layer (CBL, 130) disposed under the second conductivity type semiconductor layer; an ohmic layer forming transparent electrode disposed under the second conductivity type semiconductor layer, the transparent electrode directly contacting the second conductivity type semiconductor layer and surrounding side surfaces and under surface of the CBL; a reflective electrode disposed under the second conductivity type semiconductor layer, the reflective electrode directly contacting the second conductivity type semiconductor layer, and surrounding side surfaces and under surface of the transparent electrode; a channel layer made of a metal disposed under the light emitting structure and surrounding side surfaces and under surface of the reflective electrode; and a support substrate connected to the channel layer through an adhesive layer, wherein the current blocking layer faces the first electrode, an upper surface of the current blocking layer is disposed on the same line as a lower surface of the second conductivity type semiconductor layer, the channel layer separates the passivation layer from the reflective electrode, the passivation layer directly contacts the channel ayer at the outer surface of the light emitting structure, and the channel layer directly contacts the reflective electrode.