A camera system comprises a camera body; a lens barrel having a photographing optical system, which can be mounted at the camera body; a shutter release switch disposed at the camera body and operated to start a shutter release operation; and a first operating switch related to an operation of the camera system other than the shutter release operation. The first operating switch is disposed at the lens barrel so as to allow an operator to perform a batch operation of the shutter release switch and the first operating switch with the lens barrel mounted at the camera body.