The complex permittivity of different types of soils in the ultrahigh frequency (UHF) is studied in this letter. A new model, whose inputs are the low-frequency conductivity and the volumetric water content, is proposed to estimate the complex permittivity of soils in UHF. The model is compared with complex-permittivity values of each soil in the UHF range, which are determined from two-port <inline-formula> <tex-math notation="LaTeX">$S$ </tex-math></inline-formula>-parameters measurements of a coaxial probe designed for material characterization. Results show that the model is in a good agreement with the measurements despite some differences in soils with high resistivity. The soil samples used in this study include locations where humanitarian demining operations are being conducted.