Abstract: The temperature characteristics of main physical parameters of a fence structure capacitive micromachined accelerometer are investigated by theoretical analysis and experiment. The experimental results show that the two initial sensing capacitances change with temperature and their variations are different from each other. Based on the temperature characteristics of the accelerometer and its interface circuit, the system-level simulation model is built on Simulink platform. The simulation results demonstrate that the mismatch between the different variations of the two initial sensing capacitances as temperature changing is the major influencing factor to the temperature performance of the accelerometer system. The greater the mismatch degree is, the more serious the temperature effect on the system becomes. The temperature performance of the accelerometer system is improved from -6.245 to -2.1 mg °C-1 by adopting thermal resistance as the gain resistance of the instrumentation amplifier, without any additional hardware circuit or software algorithm.