The method for tracking deformation of a metal part subjected to a pressure force (F) includes the steps of measuring the displacement (d) of the metal part in the deformation zone, of measuring the intensity of the pressure force (F), of calculating, during a first period, the constant ratio (α) between the intensity of the pressure force (F) and the displacement (d) of the metal part, and of determining, during a second period, displacement values (de) and (dp) related respectively to an elastic deformation and to a plastic deformation of the metal part from the constant ratio (α) and a displacement (da) measured during the said second period.