Abstract It is the temperature field of the closed cavity that plays a decisive role in sensitive inclination. With numerical simulation of ANSYS, the temperature field was analyzed separately under the environmental temperature and heat source temperature unchanged. When the temperature difference between environment and heat source remains constant, the temperature gradient of flow field remains invariant. A circuit can be designed so that the temperature difference between the environment and the heat source does not change during the operation of the inclination sensor, and improving the stability of sensor performance further with the circuit.