A portable endoscope system including an illuminating light guide for transmitting light for illuminating an object, and an illuminating light supply unit for supplying illuminating light to the illuminating light guide. The entrance end portion of the illuminating light guide is disposed in an endoscope control part. The illuminating light supply unit is detachably attached to the control part. The portable endoscope system includes an AC/DC conversion adapter which is connected to an AC power supply to output a predetermined DC voltage and is connectable to the illuminating light supply unit.