To provide a double lock device for door lock conformable to various diameters of the base narrow diameter parts of handles and mountable on substantially all handles.

This device comprises a cup-like body 1 for covering the handle T of a door lock mounted on a door D; a pair of ring members 2 and 3 fixed on one-end sides to the opening part 1a of the cup-like body 1 and mutually rotatably overlapped; a plurality of claw members 4 rockably fixed on the base end side to one ring member 3; a claw guide mechanism 5 for gradually moving the tip side 4a of the claw member 4 to the inside of the ring members 2 and 3 according to the relative rotation of the ring members 2 and 3; and a lock 6 for fixing the claw member 4 in an optional position.