With the aim to improve measuring sensitivity,enlarge dynamic detection range and to realize the temperature compensation of microflow sensors in microfluidic systems,a novel pressure microflow sensor based on Lamb waves is set up in this paper. The sensor mainly composed of two Lamb wave sensors connecting by a microchannel. Based on the sensitive properties of the film stress in the lamb sensors and the relationship between the frequency output and the pressure in a proportion,the sensing system measures directly the frequency output of each sensor to obtain the pressure difference between two ends of the microchannel and also construct a different frequency measurement structure between two Lamb wave sensors to realize the temperature compensation. For a microchannel with 20 mm in length,1 mm in width and 50 μm in high,experimental results indicate the frequency difference between two Lamb wave sensors varies linearly with the flow,and the linear correlation coefficient is 0.999 9. Before optimization of the microflow sensor mentioned above,the minimum detectable flow is 0.627 μL/s.