A subretinal prosthetic device comprising: a substrate provided under a retina; a return electrode for receiving a current such that a ground is formed on the substrate; a plurality of photodiodes for outputting a dark current in response to external visual information projected onto the retina; a plurality of stimulating electrodes provided on the substrate and for generating an active potential to an optic nerve in response to external visual information projected onto the retina, the plurality of stimulating electrodes comprising a plurality of conversion circuits connected to the plurality of photodiodes, respectively, for converting the dark current into a current signal suitable as the active potential; and a plurality of switches for controlling the current between each of the plurality of stimulating electrodes and the return electrode, the plurality of switches being connected between the plurality of stimulating electrodes and the return electrode, respectively, to ground the plurality of stimulating electrodes to the return electrode in response to an on or off control signal, characterized in that the substrate further comprises a control module configured as a scanning array for setting a portion of the plurality of stimulating electrodes included in a portion of a region in which the plurality of stimulating electrodes are arranged, switching from the portion of the plurality of stimulating electrodes of the scanning array to the return electrode, and setting, as the scanning array, another portion of the plurality of stimulating electrodes included in another portion of the region. a substrate provided under a retina; a return electrode for receiving a current such that a ground is formed on the substrate; a plurality of photodiodes for outputting a dark current in response to external visual information projected onto the retina; a plurality of stimulating electrodes provided on the substrate and for generating an active potential to an optic nerve in response to external visual information projected onto the retina, the plurality of stimulating electrodes comprising a plurality of conversion circuits connected to the plurality of photodiodes, respectively, for converting the dark current into a current signal suitable as the active potential; and a plurality of switches for controlling the current between each of the plurality of stimulating electrodes and the return electrode, the plurality of switches being connected between the plurality of stimulating electrodes and the return electrode, respectively, to ground the plurality of stimulating electrodes to the return electrode in response to an on or off control signal, characterized in that the substrate further comprises a control module configured as a scanning array for setting a portion of the plurality of stimulating electrodes included in a portion of a region in which the plurality of stimulating electrodes are arranged, switching from the portion of the plurality of stimulating electrodes of the scanning array to the return electrode, and setting, as the scanning array, another portion of the plurality of stimulating electrodes included in another portion of the region.