Abstract: A kind of inertial sensor based on natural convection is attracting more and more attentions recently. But the environment temperature has inevitable effects on property of the convection-based sensors. By numerical simulation the fluid flow in chamber of such a tilt sensor, which is changing with the environment temperature, is researched. The mechanism of influence of fluid flow on property of sensor is analyzed. A method of eliminating the influence of environment temperature on property of sensor is proposed based on the theory of flow similarity. The results show that a compensative circuit specially designed can keep flow similarity so as to eliminate the influence of environment temperature.