A silver doped modified montmorillonite was made by octadecyl trimethyl ammonium bromide（STAB） and ［Ag（NH3）2］OH,and characterized by X-ray diffraction,scanning electron microscopy and AC impedance method.The electrochemical behavior of hydroquinone on the electrode modified by the montmorillonite was investigated by cyclic voltammetry（CV）and some important kinetic parameters of the electrochemical process were determined.The results indicated that the anode process of hydroquinone at electrode was controlled by adsorption-diffusion,and the cathodic process was controlled by diffusion.The number of electron transfer was equal to the number of protons（n=m=2）,and the transfer coefficients α equals 0.658 8 and β equals 0.341 2.The effective area of Ag STAB-MMT/GCE（Aeff）was 0.026 4 cm2,and the diffusion coefficient（D）was 6.34×10-5 cm2/s.The correlation between the peak current and concentration was investigated by square wave voltammetry（SWV）.A good linearity was obtained between the peak current and the concentration of hydroquinone in the range of 4.0×10-6~5.0×10-4 mol/L,with a detection limit of 1.13×10-7 mol/L.The method was applied in the determination of hydroquinone in real water with spiked recoveries of 100%-108%.The modified electrode showed good reproducibility and stability.