The kinetic characteristics of NH₄⁺ adsorption-desorption for five major soils in shaanxi province were studied by using the continuous fluid flow method.NH₄⁺ adsorbing-desorbing equilibrium time and reaction rate,equilibrium adsorbing-desorbing capacity and adsorbing equilibrium constants changed with the soil clay content and CEC.Different kinetic models showed different fitting results to the data of experiment.First-order equation and Elovich equation were the best models for fitting to the data of NH₄⁺ adsorbing and desorbing reac-dons respectively.NH₄⁺ diffusion speed was the factor controlling the NH₄⁺ adsorbing and desorbing rates.NH₄⁺ desorbing rate increased significantly with raising temperature.