An electronic endoscope system which is configured to eliminate the necessity to mount separate airtight means on a connector section between an electronic endoscope and an external unit at a stage of washing and disinfection, and maintain electrical isolation for patients' securities at the same time. The electronic endoscope system has a composition wherein an electronic endoscope which is equipped with a CCD is connected by way of a connector to a light source unit which is equipped with a light source and performs output control of at least video signals, signal transfer between the electronic endoscope and the light source unit is performed with optical elements, and electric power is supplied from the light source unit to the electronic endoscope by spatial electromagnetic means. Electric power obtained by the electromagnetic coupling means is accumulated once in a battery and the electronic endoscope is driven by the battery. In the electronic endoscope, output signals from the CCD are used as inputs for generating almost completed video signals which are to be used as monitor output video signals by a DSP.