Abstract: Method for compensating the drift of a gyro mounted on a vessel subjected to at least rotational motions, about horizontal axes centered around an equilibrium position, and vertical translational motions, which vessel includes a three-axial accelerometer for measuring the acceleration of the vessel along three directions, includes low pass filtering the output signal from the gyro, calculating an inclination signal based upon the measurement values of the accelerometer and low pass filtering it, compensating the output signal from the gyro based upon the difference between the two low pass filtered signals, selecting the cut-off frequency of the low pass filtration of the inclination signal so that it is larger than a typical oscillation frequency for the translational motions but smaller than a typical oscillation frequency for the rotational motions, calculating a total force vector from the three measurement values, and calculating the inclination signal based upon the total force vector.