To provide a rotary joint in which entire length may be less even in the case of many number of air circuits and the restriction of the carriable mass of the wrist of a manipulator may be less.

The joint is provided with a rotary connection body 2 composed by projecting a disc part 5 on a spindle whose base part is installed on the rotary drive part 61A of the wrist tip of an arm and on whose tip part the mount 9 for installing a hand 62 is formed and a fix side disc body 11 supported rotatably around the rotary connection body 2 and also connected to the fixed part 61B of the wrist tip and whose side surface is facing to the disc part 5. On the facing surface part of the disc part 5 to the fixed side disc body 11, plural sealed ring grooves 17 with a different diameter are provided concentrically and air input ports 18 communicating with respective ring grooves 17 are provided on the fixed side disc body 11 and air output ports 26 communicating with respective ring grooves 17 through a communication passage are provided on the spindle part.