An electronic endoscope in which images of an object to be viewed are picked-up in a field-sequential system by a solid-state image pickup device. The electronic endoscope includes a primary converter for converting different color image signals picked-up by the solid-state image pickup device and successively output therefrom, into digital image signals. A single memory temporarily stores the digital image signals in a point-sequential system. A secondary converter converts the digital image signals successively read from the single memory, into analog image signals. A delay delays a part or all of the analog image signals by different delay times to synchronize the color image signals.