An endoscope comprising: an insertion section including a bending section configured to perform a bending motion and extending in longitudinal directions; an operation section body provided to a proximal direction side of the insertion section; a bending operation input unit (11A-11F) including a bending operation input section (18A-18F) configured to input a bending operation to bend the bending section, wherein the bending operation input unit (11A-11F) is removably attached to the operation section body; an activated portion (22A-22D, 46A-46D, 61A-61D) provided in the bending operation input unit (11A-11F) and configured to change its activated state in response to an input state of the bending operation; and a drive member provided in the operation section body and configured to be driven to bend the bending section, characterized by an activated state detector (26A, 27, 51A-51D, 62A-62D) provided in the operation section body, configured to detect the activated state of the activated portion (22A-22D, 46A-46D, 61A-61D), and electrically insulated from the activated portion (22A-22D, 46A-46D, 61A-61D); a control method input section (23, 53, 63) provided in the bending operation input unit (11A-11F) and configured to input a type of the bending operation input unit (11A-11F); and a control method detector (26B, 37, 57, 65) provided in the operation section body, configured to detect a type of the bending operation input unit (11A-11F), electrically insulated from the control method input section (23, 53, 63) and configured to select a bending control parameter, by which a relationship between an input value of the bending operation and a bending amount of the bending section is determined, in accordance with the type of the bending operation input unit (11A-11F), and thereby configured to detect a control method of the bending operation corresponding to the selected bending control parameter, wherein the drive member is configured to be driven in accordance with the control method detected by the control method detector (26B, 37, 57, 65) and the activated state detected by the activated state detector (26A, 27, 51A-51D, 62A-62D). an insertion section including a bending section configured to perform a bending motion and extending in longitudinal directions; an operation section body provided to a proximal direction side of the insertion section; a bending operation input unit (11A-11F) including a bending operation input section (18A-18F) configured to input a bending operation to bend the bending section, wherein the bending operation input unit (11A-11F) is removably attached to the operation section body; an activated portion (22A-22D, 46A-46D, 61A-61D) provided in the bending operation input unit (11A-11F) and configured to change its activated state in response to an input state of the bending operation; and a drive member provided in the operation section body and configured to be driven to bend the bending section, characterized by an activated state detector (26A, 27, 51A-51D, 62A-62D) provided in the operation section body, configured to detect the activated state of the activated portion (22A-22D, 46A-46D, 61A-61D), and electrically insulated from the activated portion (22A-22D, 46A-46D, 61A-61D); a control method input section (23, 53, 63) provided in the bending operation input unit (11A-11F) and configured to input a type of the bending operation input unit (11A-11F); and a control method detector (26B, 37, 57, 65) provided in the operation section body, configured to detect a type of the bending operation input unit (11A-11F), electrically insulated from the control method input section (23, 53, 63) and configured to select a bending control parameter, by which a relationship between an input value of the bending operation and a bending amount of the bending section is determined, in accordance with the type of the bending operation input unit (11A-11F), and thereby configured to detect a control method of the bending operation corresponding to the selected bending control parameter, wherein the drive member is configured to be driven in accordance with the control method detected by the control method detector (26B, 37, 57, 65) and the activated state detected by the activated state detector (26A, 27, 51A-51D, 62A-62D).