An endoscope system includes: an insertion portion in which an image pickup unit configured to pick up an image of an object to be examined and generate a video signal is disposed in a distal end； a video processor configured to process the video signal generated by the image pickup unit； and a signal transmission path connecting the image pickup unit and the video processor, and at least a part of the signal transmission path is a waveguide configured to allow propagation of a millimeter wave or a submillimeter wave, and signal transmission is performed by the waveguide.
