An endoscope system according to the present invention includes: a CMOS imaging element; a timing generator and an AFE unit that are provided on a board connected to a light receiving unit and reads pixel information by causing the pixel information to be output from a pixel designated as a target to be read in the CMOS imaging element; a control circuit that is provided on the board and controls a pixel information output process by a light receiving unit and a pixel information reading process by the timing generator and the AFE unit; and an abnormality determining unit that determines whether there is an abnormality in the pixel information read by the timing generator and the AFE unit and outputs, to the control circuit, a notification signal for causing the control circuit to execute control on an occurrence of the abnormality.