To provide a camera adapter firstly, with which a portable camera usually carried by hand for outdoor recording or the like can be used as a studio camera instantly by one touch operation in a simple and easy way, and by which, in the next place, secondly large cost cut is realized and shortage of studio cameras can be solved.

The camera adapter 1 includes a mounting unit 3 of a portable video camera 2, the portable video camera 2 which is mounted on the mounting unit 3, a mounting unit 5 of a viewfinder, the viewfinder which is mounted on the mounting unit 5, a broadcasting tarry lamp 6, an intercom function, a connector panel 9 used for signal transfer in these cases, an electronic circuit unit 10 used for the signal processing, and a call tarry lamp. The camera is used for program production in a studio and operated by a cameraman, while it is controlled by a producer in a control room.