A system for measuring electrical impedance in human tissues comprising a plurality of needles (10)； said plurality of needles (10) being arranged along a circumference； where said plurality of needles (10) have a length greater than 0.5 cm； said plurality of needles (10) being coated with an electrically insulating material throughout their entire length except for a portion (12) having a maximum length of 0.5 mm； each of said plurality of needles (12) being connected to a multiplexer (15)； an alternating-current generator (20) being connected to an input of said multiplexer (15)； where said current generator (20) sends a current (21) at at least two different frequencies ranging between 10 Hz and 1 MHz； a voltmeter (22) being connected to an output of said multiplexer (15), a control centre (25) connecting selectively and in succession said current generator (20) to first two needles of said plurality of needles (10)； said control centre (25) controlling said multiplexer (15) so as to connect selectively and in succession said voltmeter (22) to second two needles of said plurality of needles (10) according to a predefined scheme； said control centre (25) measuring the impedance between said second two needles at said at least two frequencies； said control centre (25) calculating an image, having a size substantially-equal to that of said circumference, for each of said at least two frequencies corresponding to said measurement of the impedance between said second two needles； said control centre (25) supplying said image to a system for displaying (26) said image.L'invention concerne un système de mesure d'impédance électrique dans des tissus humains, comprenant une pluralité d'aiguilles (10) ； ladite pluralité d'aiguilles (10) étant agencée le long d'une circonférence ； ladite pluralité d'aiguilles (10) ayant une longueur supérieure à 0,5 cm ； chacune de ladite pluralité d'aiguilles (10) étant revêtue d'un matériau électriquement isolant sur toute sa longueur à l
