A one-dimensional experiment of adsorption of biogas slurry by unsaturated homogeneous soil at constant room temperature was conducted in order to investigate the adsorption characteristics of total nitrogen from biogas slurry. The conductivity and total nitrogen content of percolates were measured with different concentrations of biogas slurry, soil densities, and infiltration heads of biogas slurry. The average pore-water velocities and hydrodynamic dispersion coefficients under different experimental conditions were obtained through fitting of the experimental data using the convection-dispersion model of solute transport and CXTFIT2. 0 software. The experimental results showed that the peak values of the conductivity of percolates in experimental schemes with higher soil density was less than those in schemes with lower soil density; the differences between the peak conductivity of the percolates and the conductivity after the peak point increased with the concentration of the biogas slurry; with the increase of the biogas slurry concentration, the adsorption curves gradually moved towards the right, and the time corresponding to the turning point of adsorption curve and the total nitrogen content in soil increased, but the relative concentration of the percolate at the turning point, the average prove-water velocity, and the hydrodynamic dispersion coefficient decreased under the same soil density and head conditions; with the increase of the infiltration head, the time that the soil needed to reach saturation of the adsorbed total nitrogen decreased, and the average pore-water velocity and hydrodynamic dispersion coefficient increased under the same biogas slurry concentration and soil density conditions; and, with the increase of soil density, the time corresponding to the turning point of adsorption curves and the hydrodynamic dispersion coefficient increased, but the average pore-water velocity decreased under the same biogas slurry concentration and head conditions.