In order to investigate the effects of biochar on the adsorption and desorption characteristics of cadmium (Cd) elements, the adsorption kinetics, isothermal adsorption and desorption of Cd²⁺ in red soil paddy soils amended with biochar were studied by a primary equilibrium method. The results showed that after applying biochar of CK (0 t/hm²), A10 (10 t/hm²), A20 (20 t/hm²), A30 (30 t/hm²) and A40 (40 t/hm²), the adsorption of Cd²⁺ in red paddy soil was dominated by chemical adsorption and heterogeneous multi-surface adsorption. The maximum contents of adsorption and desorption of each treatment were between 2 933~3 346 mg/kg and 171~192 mg/kg, respectively. The biochar enhanced the adsorption and fixation capacity for Cd²⁺ in red paddy soil and improved the buffer capacity for Cd²⁺. The improvement of adsorption and desorption capacity in red paddy soil amended with biochar was shown as follows:A30 > A40 > A20 > A10. High addition of biochar could saturate the soil adsorption point. Therefore, the adsorption capacity of biochar was relatively low. In conclusion, addition of 30 t/hm² biochar was the most reasonable measure.