To provide a caulking tool which is particularly small-sized and easy to be carried for fixing a cable to a shell.

This caulking tool is provided with a body 51 comprising a frame body at the lower part of the inner peripheral face of which a die 52 is formed and at the upper part of which a screw hole 66 is formed, a cable guide 58 disposed on the body so that the upper face of the die and a cable support slit 59 are nearly flush with each other, an L-shaped stopper 61 one end of which is fixing set on the side face of the body so as to be turnable in the vertical direction of the body on demand, a punch 53 having a plunger 55 slidable in the vertical direction touching the inner peripheral face of the body, which has a recessed part 54 into the lower end part of which both sides of the die can be fitted, protruding nearly the center part of the recessed part and retreating by required pressure, a pusher 65 which is threadedly engaged with the screw hole 66 of the body and by the lower end coupling part of which the punch is moved in the vertical direction, and a bar 68 turning the pusher.