To provide a lens barrel capable of executing an automatic focusing operation and a manual focusing operation without affecting a motor driving part.

The device is provided with rotor connecting members 20 and 22 for transmitting the rotation of a rotor member 18 in frictional connection with the rotor member 18, a manual connection member 25 for transmitting the manual rotation, rollers 24 which are arranged at three or more positions on a circumference around the optical axis of the lens and also which are rotated around supporting, shafts arranged in the radial direction of the optical axis and which are rotated while being held between the manual connection member 25 and the rotor connection member 22, and an output ring 23 which is rotated while transmitting the rotation of the roller 24 around the optical axis. When a load equal to or exceeding the prescribed one by which the rotation is interrupted is applied on the output ring 23, a slippage is generated between the rotor member 18 and the rotor connection members 20 and 22 so as not to transmit the rotation.