Diabetes mellitus is a chronic but treatable disease affecting about 200 million people around the world [1].For these patients,regular measurements of blood glucose levels are required to confirm whether the treatments are working effectively.Noninvasive route for continuous glucose monitoring is highly expected to eliminate pain and discomfort.So,noninvasive glucose sensing is the ultimate goal for routine glucose monitoring.Saliva is a relatively good candidate for noninvasive determination of glucose,however,the concentration of glucose in saliva is very low,usually from 30 to 80 μM,[2],obviously lower than the detection limit of normal gloucose senors for blood,which thus inspired us to exploit glucose sensors with lower detection limit.Here,we report on a novel nonenzymatic amperometric glucose sensor based on CuO nanoneedle/graphene/carbon nanofiber modified glassy carbon electrode (CuO/rGO/CNF/GCE).The results of the scanning electron microscopy indicating that electrical network was formed through their direct binding with the rGO/CNF which leads to large active surface areas and fast electron tansfer for the modified glucose sensor.High electrocatalytic activity toward oxidation of glucose was observed with a rapid response (ca.3 s),a low detection limit (0.1 μM),a wide and useful linear range (1 μM-5.3 mM) as well as good stability and repeatability.Moreover,the common interfering species,such as ascorbic acid,uric acid,dopamine and so forth did not cause obvious interference.The sensor can also be used for quantification of the concentration of glucose in real saliva samples.Therefore,this work has demonstrated a simple and effective sensing platform for nonenzymatic detection of glucose.