A glucose amperometric biosensor has been prepared by a multilayer deposition on a glassy carbon elec- trode of Co 3 Mn-CO 3 layered double hydroxide, glucose oxidase (GOx) and a biopolymer (carrageenan), respectively. The original transduction step consists in the electrocatalytic oxidation of H 2 O 2 , enzymat- ically formed, in the Co 3 Mn-CO 3 inner-layer at 0.65 V/Ag-AgCl. The sensitivity and the detection limit, obtained with this optimized bioelectrode (Co 3 Mn-CO 3 /GOx/carrageenan, 30/20/10 μg), are 12.8 mA M −1 cm −2 and 0.02 mM, respectively. A 3D-porous bioelectrode was also prepared by impregnation of a car- bon felt (CF) with a colloidal suspension of Co 3 Mn-CO 3 nanoparticles and then with GOx. The structure and the morphology of the Co 3 Mn-CO 3 /CF composite were characterized by X-ray diffraction and electron scanning microscopy and the bioelectrode GOx/Co 3 Mn-CO 3 /CF was finally tested in cyclic voltammetry in the presence of glucose.