An endoscope system includes: a photoelectric conversion element; a contour enhancing section that detects an edge component in a picked-up image subjected to the photoelectric conversion, thereby generating a contour enhancement signal; an electronic zoom region determining section that determines an electronic zoom region in the picked-up image based on a strength of the contour enhancement signal; an instruction section that provides an instruction for enlargement/reduction of the image; a parameter setting section that sets a zoom parameter for an electronic zoom section according to the instruction provided by the instruction section; and the electronic zoom section that performs an electronic zoom of the picked-up image for the electronic zoom region determined, according to the parameter set by the parameter setting section.