Abstract: In view of the problem that the current liquid sensor is interfered by various environmental factors leading to abnormal monitoring of flammable liquid concentration,which leads to safety risks,we designed a liquid concentration sensor combining metamaterial differential structures with integrated microfluidic devices and RF sampling circuits. The sensor’ s structure was determined through electromagnetic simulations and equivalent circuit analysis. In the experiment,the sensitivity of the sensor to the ethanol solution of 0 to 100% water volume fartion was measured,and the stability and validity of the voltage data sampled by the RF sampling circuit were also verified. The experimental results show that the sensor sensitivity reaches 10. 2 MHz / Δε_r,and the designed sensor realizes the high precision detection of flammable liquid concentration in complex environment. The mathematical model is fitted with the experimental data to obtain the accurate concentration value,and the maximum measurement error is 0. 20%. The designed sensor has strong anti-interference ability,enabling accurately detect the concentration of flammable liquid,and can be widely used in the field of concentration monitoring of flammable liquid and other solutions in various complex environments.