Marine shafting positioning tool

The utility model provides a marine shafting positioning tool. The marine shafting positioning tool comprises a support tube, a sighting instrument is arranged in the inner hole of the support tube, the datum point of the sighting instrument is corresponding to the datum point of a light target arranged at the bow, at least two adjustment rings are sleeved on the support tube in a spaced manner, the periphery of each adjustment ring is uniformly provided with four screw holes, and screws for adjusting the position of the support tube are inserted in the screw holes. The marine shafting positioning tool provided by the utility model has the advantages of high precision, strong operability, low cost and the like. During installation of auxiliary equipment, multiple functions of wire drawing, illumination and equipment installation can be realized, and the datum point at the bow can be brought into the monitoring range, thereby ensuring required installation precision of shafting positioning equipment and quality of shafting installation.