In the present study an electrochemical sensor has been produced for measuring riboflavin with high sensitivity and selectivity. Deferential pulse technique has been used to measure the current of riboflavin on the modified glassy carbon electrode. At first, the synthesis of the GO/Au/polyEAmVS nanocomposite was performed. Synthetic nanocomposite was characterized by TEM and XRD methods and it was used for modification of glassy carbon electrode. Effective conditions were optimized for the measurement of riboflavin including pH and buffer concentration and modifier concentration. Calibration curve was linear in the concentration range of 1.0–100.0 μM under optimal conditions. A detection limit of 7.2 × 10–2 μM and relative standard deviation of 3.79% have been obtained. The prepared sensor has a good performance for measuring the amount of riboflavin in drink real samples.