【Objective】 This study aimed to provide a theoretical basis for reducing soil Cd pollution through the application of alkaline fertilizer.【Method】Field and constant temperature incubation experiments were carried out to study the effect of alkaline fertilizer on soil acidification, Cd pollution, and the effect of soil pH on the thermodynamic properties of soil Cd adsorption and desorption.【Result】Application of alkaline fertilizer significantly (P < 0.05) increased the soil pH and reduced the content of available Cd. This shows that soil treatment with alkaline fertilizer is an effective and reliable measure to reduce soil available or extractable Cd. When the ambient Cd concentration was ≤60 mg·L^–1, pH values from 5.0 to 9.0 had almost no effect on the adsorption strength of Cd (between 15.77 mg·kg^–1/mg·L^–1 and 16.67 mg·kg^–1/mg·L^–1) while Cd concentrations > 60 mg·L^–1 showed increased adsorption strength as the pH was increased. Nevertheless, the adsorption rate decreased with the increase in the initial concentration of Cd. Under the same Cd concentration conditions, the higher the pH value, the higher the adsorption capacity and adsorption rate of Cd. The Freundlich, Langmuir, and Temkin equations fitted the Cd isothermal adsorption data well. Of all three equations, the Freundlich equation had the best fit and was the most suitable to quantitatively describe the characteristics of Cd adsorption. The adsorption of Cd was a spontaneous process and characterized by a negative adsorption free energy (△G^ｏ). Importantly, △G^ｏincreased with an increase in Cd concentration at constant pH whereas △G^ｏdecreased with an increase in soil pH. Under alkaline conditions, △G was lower than under acidic conditions. However, Cd adsorption was more intense under alkaline conditions than in acidic conditions. This shows that increasing the soil pH with alkaline fertilizer was beneficial in improving the Cd adsorption capacity of the soil. At relatively low Cd concentration, Cd adsorption occurred through the specific adsorption mechanism. When the degree of Cd contamination was high and at high pH, the variable charge of the soil and its non-obligate adsorption played a positive role. Furthermore, the Cd desorption capacity and the rate decreased significantly (P < 0.05) after the application of alkaline fertilizer. 【Conclusion】 At constant pH and increasing Cd concentration, the adsorption capacity of Cd and the free energy increased while the adsorption rate decreased. Also, at higher soil pH, the adsorption capacity, adsorption rate, and reaction free energy were significantly increased while the desorption rate was decreased. There was a negative correlation between soil pH and the availability of soil Cd. Increasing the soil pH can enhance the ability of soils to fix and passivate Cd, thus, reducing the bioavailability of Cd. It is suggested that alkaline fertilizers should be applied in agricultural practices to manage soil acidification, improve soil pH, increase heavy metal cations adsorption and reduce their bioavailability in soils. This will help to control soil acidity and reduce heavy metals pollution in agro-production.