A disposable glucose biosensor was prepared using nanoparticles of MnO2 decorated on graphene nanoribbons by surface modification with drop coating with the GOx and Nafion (R). Tested material was synthesized and characterized using several techniques. The biosensor could be operated under physiological conditions (0.1 M phosphate buffer, pH 7.4) and exhibited good reproducibility and stability. The linear range for the amperometric response of the biosensor at operating potential of +0.50 (versus Ag/AgCl) was from 0.1 to 1.4 mmol/l, with a detection limit of 0.05 mmol/l and high sensitivity of 56.32 mu A/mmol cm(2). Developed method was tested toward glucose quantification in real samples with satisfactory accuracy and precision.