The study of hydraulic characteristics in unsaturated soils is crucial for analyzing seepage and deformation of loess during engineering activities. This research focuses on loess from the southern suburbs of Xi’an City. The filter paper method and saturated salt solution method were employed to measure soil-water characteristic curves under three dry density conditions with varying degrees of wetness. The Childs & Collis-George model was used to predict unsaturated permeability coefficient, examining the impacts of dry density and wetting/drying cycles on these characteristics. Results indicate that unsaturated permeability coefficient increased with volumetric moisture content and decreased with matric suction, dropping significantly by 4-5 orders of magnitude within the 0-5 MPa range. Due to bottleneck effects and moisture-reduction-induced shrinkage, the variation in permeability coefficient during wetting stages was smaller compared to drying stages. Furthermore, with dry density increasing from 1.719 g/cm³ to 1.834 g/cm³, permeability coefficient decreased by two orders of magnitude. The unsaturated permeability coefficient of compacted loess varied by a factor of up to 3-4 between wetting and drying phases.