A glucose amperometric biosensor has been prepared by a multilayer deposition on a glassy carbon electrode of Co3Mn-CO3 layered double hydroxide, glucose oxidase (GOx) and a biopolymer (carrageenan), respectively. The original transduction step consists in the electrocatalytic oxidation of H2O2, enzymatically formed, in the Co3Mn-CO3 inner-layer at 0.65 V/Ag-AgCl. The sensitivity and the detection limit, obtained with this optimized bioelectrode (Co3Mn-CO3/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 carbon felt (CF) with a colloidal suspension of Co3Mn-CO3 nanoparticles and then with GOx. The structure and the morphology of the Co3Mn-CO3/CF composite were characterized by X-ray diffraction and electron scanning microscopy and the bioelectrode GOx/Co3Mn-CO3/CF was finally tested in cyclic voltammetry in the presence of glucose.