A method of determining the angular position of a first rotor of a turbojet. A vibration pulse is generated during a rotation of the first rotor, each vibration pulse being generated when the first rotor passes through a given reference angular position. The vibration generated is detected. The angular position is obtained at a given instant of a second rotor of the turbojet relative to the angular position that it occupied at a reference instant representative of detecting a vibration pulse. The second rotor is coupled in rotation with the first rotor and has a speed of rotation different from the speed of rotation thereof. The angular position of the first rotor at the given instant is determined from the angular position of the second rotor.