A chlortoluron molecularly imprinted sensor was prepared on the surface of platinum oxide electrode through chemical polymerization.Gate’s change in the quantity of “gate-controlled” was utilized for manipulation of catalytic performance，combining with the catalytic amplification effect of platinum oxide on hydrogen peroxide.The sensitivity of sensor was improved effectively and the detection method for chlortoluron residue in environment was developed.In addition，the catalytic effect of platinum oxide electrode to hydrogen peroxide and the polymerization ratio of molecular imprinted membrane were studied.The hydrogen peroxide concentration,elution time and the re-adsorption time were optimized.Under the optimal conditions，the concentration of chlortoluron was negatively correlated with intensity of the catalytic current of platinum oxide electrode in the range of 1.0×10-8-8.0×10-6 mol/L，and the detection limit was 5.4×10-9 mol/L.The sensor was successfully applied in the detection of farmland water with recoveries of 98.5%-102.0%.