An endoscope power supply system includes an endoscope including an imaging unit that images an object, a housing apparatus to which the endoscope is detachably connected, a plurality of power source units that are provided in the housing apparatus and configured to output electric power different from one another, switches each provided in an output stage of each of the power source units of the housing apparatus and formed of two FETs that are back-to-back connected, and a controller that is provided in the housing apparatus, selects a power source unit necessary to operate the endoscope from the power source units, and controls the switches to output electric power generated by the selected power source unit to the endoscope