Abstract: Based on a MEMS microcalorimetric chip of model number NCM9924, a calorimetric biosensor experimental system for the determination of residual amounts of pesticide was established using chicken liver esterase as biological sensitive element. By means of this system, thermo-sensitivity of the calorimetric chip,heat release of the enzymatic reaction and inhibition by pesticide were studied. The results showed that temperature sensitivity of the transducer was not lower than 1.184 mV·K-1 at flow rate of 0.5 mL·min-1 and the reproducibility of the system response to heat release was good. The peak height of the heat release curve was reduced by 50% when the chicken liver esterase was inhibited by 2 mg·L-1 methamidophos.