The invention discloses a dedicated clamping tool for an anchor chain measurement sensor sheath of a deep sea platform, and the clamping tool comprises a lateral cross beam, two hooks fixed at the topof the cross beam, a holding frame which is fixedly disposed on a side surface, opposite to the direction of the hooks, of the cross beam, a bidirectional screw which is parallel to the cross beam and can be rotatingly disposed in the cross beam, a left lock hook and a right lock hook which are each provided with a threaded hole, and a positioning block which is disposed on a side surface, at thesame side as the holding frame, of the cross beam. The bidirectional screw is symmetrically provided with a left-hand thread and a right-hand thread. The left lock hook and the right lock hook are respectively screwed on the left-hand thread and the right-hand thread through the threaded holes, and stretch out of the other side surface, opposite to the holding frame, of the cross beam. The rotating of the bidirectional screw just can enable the left and right lock hooks to get close to each other or separate from each other in a manner of sliding left and right relative to the cross beam. A positioning block is provided with a sensor sheath installation port and a U-shaped groove.