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Piezoceramic materials like PZT allow the manufacturing of piezoelectric sensors with advantages including high sensitivity, low price, and easy to shape. However, it is also featured with the pyroelectric effect, which brings extra charge generation with temperature variations. Those charges caused by the thermal effect contribute to errors in the sensor measurement result. Theoretically, the appropriate configuration of the sensor would neutralize the thermal effect. In this thesis, a triple layer piezoelectric sensor with a parallel connection would be used to check its thermal stability at elevated temperatures. The thesis begins with reviewing the fundamental concepts of piezoelectricity. The following section contains the analysis of the relationship between the different external inputs and the output of a triple layer sensor. The experiment is designed to put the triple layer sensor in a chamber with a temperature control system to test its performance at around 35 ℃ with sinusoidal excitation input. A unimorph sensor would be set as the reference group, so that the result of the triple layer sensor could have a comparison with. The cancellation of the temperature effect in the triple layer sensor successfully reduces the output deviation to an acceptable level. Meanwhile, the unimorph structure sensor exhibits obvious instability under the same conditions.