1. A device for analyzing the gait of a person, the device comprising a magnetometer for fastening to a tibial segment of said person, in order to generate a signal representative of at least one projection onto a sagittal plane of an ambient magnetic field in which it is immersed; the device also comprising signal processor means for identifying instants and/or phases that are characteristic of the gait of said person by identifying particular points in the expression as a function of time for said signal generated by said magnetometer.