A camera system having a camera body and an interchangeable lens is made more convenient to use. A camera system 1 includes an interchangeable lens unit 2 and a camera body 3. A body microcomputer 10 of the camera body 3 decides whether or not the interchangeable lens unit 2 is compatible with moving picture mode on the basis of lens information about the interchangeable lens unit 2. If the interchangeable lens unit 2 is not compatible with moving picture mode, the body microcomputer 10 prevents the operation of an imaging sensor 11 from being set to moving picture mode.