A chitosan graphene oxide self assembled films modified glass carbon electrode was prepared and characterized by the electrochemical impedance spectroscopy(EIS).The behaviors of SudanⅠon the modified electrode were investigated by cyclic voltammetric method.The results indicated that an oxidation peak was observed on the modified electrode and no reduction peak was found,which showed that the electrochemical reaction of SudanⅠon the electrode was an irreversible process.The oxidation peak currents were linear to scan rates in the range of 50-250 mV?s-1,indicating that the electrode process was controlled by absorption.The numbers of electron and proton transferred in the electrode reaction were both 1.The modified electrode showed a good linear current response to SudanⅠin the range of 6.0×10-8-5.0×10-6 mol/L by differential pulse voltammetry with a correlation coefficient of 0.995 and a detection limit of 4.45×10-8 mol/L.With the advantages of simple preparation，high sensitivity，low cost，excellent reproducibility and stability，the proposed method could be used in the determination of Sudan Ⅰin salted duck egg yolk samples．