The present invention provides a camera body with high operability and a camera system with high operability including the camera body and an image pickup lens unit that is detachably mounted on the camera body. The camera body has two modes, namely, a photographing mode for receiving an image signal from the image pickup lens unit, applying signal processing to the image signal, and recording the image signal and a reproduction mode for reading out a recorded image signal and displaying an image based on the image signal on a display screen and includes a mode switching section that switches these two modes freely according to operation.