Abstract: A novel glucose biosensor electrode was fabricated by loading a glassy carbon electrode with a 1-methyl imidazole-based ionic liquid-functionalized graphene/carbon nanotube (CNTs) composite, which was used to immobilize horseradish peroxidase (HRP) and glucose oxidase (GOD) for glucose detection. SEM, AFM and FTIR were used to investigate the microstructures and morphology of the electrode. The electrochemical performance of the electrode was investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Results indicate that the electrode has an excellent electrocatalytic activity towards glucose. A biosensor prepared at the optimal loading amount of the composite and HRP/GOD ratio has a linear range of 0.004-5 mM, a detection limit of 3.99×10^-7 M and a sensitivity of 53.89 μA mM^-1 cm^-2 for glucose detection with an excellent stability and reproducibility. The excellent performance of the biosensor is ascribed to the stable three-dimensional structure of the composite, where graphene sheets provide a large surface area for immobilizing the two enzymes and CNTs inserted between the graphene sheets to decrease electron transfer resistance.