The present invention relates to a Method of measuring the viscoelastic properties of biological tissues employing an ultrasonic transducer equipped with elements converting the ultrasonic waves reflected by these biological tissues into electrical signals, different elements being grouped to form sub-apertures such that the acquisition of electrical signals from the elements of the same sub-aperture is carried out simultaneously, each of these sub-apertures being intercepted by an ultrasonic wave propagation axis at an acoustic center (Ca).In conformance with the invention, such a method is characterized in that one and the same element belongs to at least two different sub-apertures and in that an acoustic center is surrounded by at least three other unaligned acoustic centers.
