An optoelectronic device and a method of manufacturing the same which the optoelectronic effect such as light emission or light reception can be increased by forming a dual-structural nano dot to enhance the confinement density of electrons and holes are provided. The optoelectronic device comprises an electron injection layer, a nano dot, and a hole injection layer. The nano dot has a dual structure composed of an external nano dot and an internal dot. The method of manufacturing the optoelectronic device comprises the steps of forming an electron injection layer on a semiconductor substrate; growing nano dot layer on the electron injection layer by an epi-growth method; heating the nano dot layer so that the nano dot has a dual structure composed of an external nano dot and an internal nano dot; and forming a hole injection layer on the overall structure.