An endoscope system of the present invention includes an image pickup section that photoelectrically converts an optical image to generate an electronic image signal, an insertion portion that incorporates the image pickup section, includes a bendable bending portion and is inserted into a subject, a lever portion that is swingable in a direction orthogonal to a central axis, held so as to be rotatable around the central axis and swung to thereby bend the bending portion, and a video processor section that receives an image signal generated by the image pickup section, generates a display image signal, performs rotating image signal processing on the display image signal in accordance with a rotation of the lever portion and outputs the processing result to an image display apparatus.