A device and method for determining an excretion flow rate of a body fluid of a person or an animal. The device includes an absorbent element equipped with at least three electrodes connected to a measuring system for measuring at least one electric parameter so as to be electrically coupled two by two and to form at least two pairs of electrodes, separating systems which include an inlet opening exposing a part of the absorbent element so as to create a diffusion path. At least two of the electrodes are first electrodes placed along the diffusion path in such a way that each of the first electrodes is at a distance from the inlet opening representative of a volume of absorbed fluid.