An electronic endoscope apparatus includes: an image pickup apparatus mounted at a distal end portion of an insertion portion; an operation portion provided consecutively at the insertion portion, with a frame member incorporated therein; and an electrical cable extended from the operation portion for connection with an external device. In the electronic endoscope apparatus, the frame member has a circuit board portion which establishes electrical connection between shields of the insertion portion and the electrical cable, and on which various electronic parts for exchanging signals with the image pickup apparatus are mounted. In spite of the arrangement of the image pickup apparatus that can acquire high-quality images at a distal end portion of the insertion portion, a size of the apparatus, in particular, a diameter of the insertion portion, can be prevented from being increased.