To provide a coupling device with safety device optimal for a rotation mechanism, such as a manipulator.

The device 1 includes a coupling body 10 to be mounted between an input shaft 3 and an output shaft 4, a flat plate cam 20 fixed to the periphery of an end on the connection side of the input shaft 3 in the coupling body 10, and a pair of operation levers 30, 30 supported so as to be locked/released to/from the flat plate cam 20 in the coupling body 10. When the input shaft 3 and the output shaft 4 are coupled for operation to transmit rotation of the input shaft 3 to the output shaft 4, and the output shaft 4 collides with an obstacle located in the operation region of the output shaft 4, the output shaft 4 is disconnected from the rotation operation of the input shaft 3.