A silicon optoelectronic device and a light-emitting apparatus using the silicon optoelectronic device are provided. The silicon optoelectronic device includes: a substrate based on an n-type or p-type silicon; a doped region formed on one surface of the substrate and doped to an ultra-shallow depth with a predetermined dopant to be an opposite type from that of the substrate to provide a photoelectrical conversion effect by quantum confinement in a p-n junction between the doped region and the substrate; and first and second electrodes formed on the substrate to be electrically connected to the doped region. The silicon optoelectronic device may further include a control layer formed on one surface of the substrate to act as a mask in forming the doped region and to limit the depth of the doped region to be ultra-shallow. The silicon optoelectronic device has excellent efficiency and can be used as either a light-emitting device or a light-receiving device. Since the optoelectronic device uses silicon as a base material, it can be manufactured at low cost.