Method for quantifying the elasticity of a material by ultrasounds, comprising the generation of one acoustic disturbance ultrasound beam (10) for the first excitation point (1), for generating a shear wave (11), a measurement of the shear wave (11) at a plurality of lines of sight placed in a region of interest (2) at different predetermined distances from the first excitation point (1), the calculation of the speed of the measured shear wave (11) and the assessment, by calculation, of a mean stiffness value of the material in the region of interest (2) on the basis of the measured speed of the shear wave (11). In the acquired image (3) a second excitation point (4) is defined, in such a position that the region of interest (2) is interposed between the first excitation point (1) and the second excitation point (4). The method for the second excitation point (4) is carried out, for calculating the speed of the shear wave (11) for the second excitation point (4), and the assessment by calculation of the mean stiffness value is carried out on the basis of the average between the speed of the shear wave measured for the first excitation point (1) and the speed of the shear wave measured for the second excitation point (4).
