Hawse pipe axis positioning device and measuring method thereof

The invention provides a hawse pipe axis positioning device and a measuring method thereof. The hawse pipe axis positioning device comprises a first semicircular protractor, a first rotating arm, a second semicircular protractor, a second rotating arm, a first sliding block and a supporting device. One end of the first rotating arm is hinged to the first semicircular protractor, the other end of the first rotating arm is fixed to the second semicircular protractor, and the position, close to one end of the second rotating arm, of the second rotating arm is hinged to a second center point of the second semicircular protractor. The first sliding block slides along the second rotating arm at the position, close to the other end, of the second rotating arm. The supporting device comprises at least three first supporting arms and three second supporting arms. By means of the two semicircular protractors and the supporting device, the technical problem that in the prior art, no hawse pipe axis positioning device ex