Electrical communication between the flavin adenine dinucleotide redox centers of glucose oxidase and glassy carbon electrode has been achieved by employing ferrocene immoblized in Nafion membrane.The glucose sensor is made by using bovine serum albumin and glutaraldehyde to immobilize glucose oxidase on Nafion-ferrocene modified electrode. It is further coated by Nafion,which is aqueous solution made from Nafion methanol solution by distilling and is not detrimental to the enzyme but to forstall electrochemically active anionic interferents such as ascorbate and urate from reaching the electrode. The Polymer coating also avoids ferrocene’s leaking and keeps the biosensor from fouling agents. The biosensor responds rapidly to glucose in less than 60 second and its calibration linear curve is from 5.0×10^-4 to 1.3×10^-2mol/L.