Abstract: In order to shorten the detection time of spectrophotometry for determination of organophosphate and carbamate pesticide residues in vegetables, the paper studied the optimum conditions when 10 minutes was chosen as the incubation time. The new criterion for the optimum conditions was put forward , that the optimum conditions was the incubation temperature and the pH when the enzyme inhibition rate was maximum, that the precondition was enzyme was on certain activation level（0.1333 min-1 ≤k1 ≤0.2667min-1 [ 1 ]）.The optimum incubation temperature was 47℃and the optimum pH of phosphate buffer was 7.7 when 10 minutes was chosen as the incubation time. The new criterion of the detection result in the optimum conditions was put forward ,that vegetable contained certain organophosphate or carbamate pesticide residues, if enzyme inhibition rate≥58%.