To provide a universal joint that is able to be suitably used for a grinding or the like.

This is a joint being interposed between a driving turning shaft 12 and a driven shaft 13 and transmitting their turning effort, and it is provided with a first chain sprocket 14, a second chain sprocket 15, of the same shape as the first chain sprocket, being clamped tight to the driven turning shaft 13 so as to be almost concentrically situated after being opposed to the first chain sprocket 14, and a double chain 16 being formed into a ring form of the same diameter with both these first and second chain sprockets 14 and 15 while made up of connecting two rows of roller chains being attached to these first and second chain sprockets 14 and 15 tightly with each other, respectively.