An endoscope system 1 includes an insertion portion 4 inserted into an object, a direct-view observation window 11a provided in the insertion portion 4 and configured to acquire a first object image from a first region of the object, a side-view observation window 11b provided in the insertion portion 4 and configured to acquire a second object image from a second region of the object which is at least partially different from the first region, and a video processor 32 configured to generate an image signal generating a second image signal from the second object image by performing image processing as well as generating a first image signal from the first object image so that a width of an image region increases as a distance from a region adjacent to the first image signal increases in a positional relationship with the first image signal.