To prepare peanut samples for dielectric properties measurement, it is necessary to determine the true density of peanut kernels. The true density of peanut kernels at different moisture content was determined by the liquid displacement method. Toluene (C7H8) was used as the displacement liquid to avoid absorption by peanut samples. Detailed measurement procedures can be found in Guo, Tang, Wang, and Tiwari (2008) and Ling et al. (2015a). The results showed that when the moisture content of the peanut kernels increased from 10% to 30% w.b., the true density was within 1.054e1.078 g cm3 (Table 2). Because the changes in peanut kernel density were negligible, the density effect of dielectric properties of the peanut kernels was not considered in this study.