In order to simulate the response of the wooden seal cover (wooden cover) and liquid to the radar wave when measuring the liquid level of the wine jar, it is necessary to understand the electromagnetic characteristics of the wooden cover and the wine. Considering the dielectric constant of the wooden cover as well as the wine, it is essential to establish a response model of the radar system. In this paper, a simplified model is established, which includes the attenuation effect of plane wave penetrating wooden cover, plane reflection effect and multilayer reflection effect model. The simulation results show that it is feasible to measure the liquid level by FMCW(FrequencyModulated Continuous-Wave) radar detection, which uses the electromagnetic waves penetrating the wooden cover from the air and then enter the wine jar.