Abstract: In order to investigate temperature property for thermal biosensor used in organophosphorous pesticide detection, the immobilized chicken liver-esterase activity and inhibition ability by dichlorvos at different temperatures were studied by using spectrophotometer. Under the real test condition, operational loss of immobilized chicken liver-esterase was observed. The results is shown as follows: enzyme reaction is affected by temperature significantly and the esterase activity reach highest at 55～60℃; when inhibition reaction time is set to 5 minutes, inhibition degree increases with pesticide concentration. The inhibition curve is close to linear at lower concentrations; the inhibition ability by dichlorvos is not acutely affected with temperature, and it reaches maximum at 50℃; it is found that operational loss of the chicken liver-esterase have similar values at different temperature. The optimum temperature of 40℃ is selected for achieving maximum reaction rate and minimum heat damage.