A thermal temperature differential flow sensor based on MEMS technology is designed and calibrated.The flow sensor is fabricated through MEMS technology. The chip structure includes an intermediate heat source resistor

four upstream and downstream temperature measuring resistances

and four environmental resistances. The heat source resistance and the upstream and downstream temperature measuring resistor and environment resistor are suspended. The working mode of the heat source is constant temperature difference. Flow value is processed through the designed hardware detection system

and transmitted to the host computer through the serial port

digital quatity output by control the system is fitted and calibrated through MATLAB on host computer. After test

the designed sensor has excellent output characteristics after calibration and can be applied to the flow measurement in industrial field.