A digital camera system is composed of a digital camera and a lens unit detachable to this digital camera. The digital camera includes a first taking lens and a first CCD image sensor to convert subject light into image data. The first taking lens is surrounded by a detachable decorative ring. When a hook release button is pressed to detach the decorative ring, a camera-side mount appears. The lens unit is attached to this camera-side mount, and photographing can be performed with a second taking lens and a second CCD image sensor in the lens unit.