Disclosed are an optical input/output device and an opto-electronic system including the same. The device includes a bulk silicon substrate, at least one vertical-input light detection element monolithically integrated on a portion of the bulk silicon substrate, and at least one vertical-output light source element monolithically integrated on another portion of the bulk silicon substrate adjacent to the vertical-input light detection element. The vertical-output light source element includes a III-V compound semiconductor light source active layer combined with the bulk silicon substrate by a wafer bonding method.