In this study, imidazole-based NHC-Au(I) complexes were prepared. Geometrically optimized structures and molecular orbital energy diagrams were computed using density functional theory. Cyclic voltammetry and amperometric methods were used to evaluate the catalytic activity of the NHC-Au(I)-modified electrodes toward glucose oxidation. The mechanism of electrocatalytic oxidation at NHC-Au(I)-modified electrodes is explained on the basis of the oxidation and reduction potentials in the presence of glucose. Applicability of NHC-Au(I)-modified electrode was extended to determine the glucose level in the blood serum and the precision of the method was found to be satisfactory. The non-enzymatic sensor exhibited excellent reproducibility, repeatability, antifouling, and anti-interference characteristics.