Aiming at the reuse of discarded rice straw and its treatment of Cd²⁺ pollution in wastewater, rice straw was modified with KMnO₄,KOH, H₂O₂, KOH+H₂O₂, tartaric acid, citric acid, and TiO₂,and made as different types of rice straw sorbentsto adsorb Cd²⁺ in solution. These adsorbents were analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD), FTIR spectrometer, specific surface area and aperture analyzer, and Zeta potentiometer. The adsorption kinetic data were fitted with pseudo-first-order, modified pseudo-first-order, pseudo-second-order and intra-particle diffusion models. The results showed that, under the condition of initial Cd²⁺ concentration of 100mg/L, pH 7, adsorbent dosage of 10g/Lrice straw and adsorption temperature of 25℃, rice straw modified with KMnO₄ had thebest Cd²⁺ adsorption in the aqueous solution, and the adsorption capacity was 10.024mg/g Cd²⁺. Its percentage of removal of Cd²⁺ reached 99.24% and had an increase of 99.44% compared with unmodified rice straw. Followed by rice straw was modified with KOH and KOH+H₂O₂,their adsorption capacity for Cd²⁺ were 9.302mg/g and 9.189mg/g, percentage of removal of Cd²⁺ reached 92.62% and 90.82%, respectively. Compared with unmodified rice straw treatment, Cd²⁺ removal of rice straw modified with KOH and KOH+H₂O₂ had increases of by 85.07% and 82.83%, respectively. The adsorption order of modified rice straw treatments was:KMnO₄ > KOH > KOH+H₂O₂ > TiO₂ > H₂O₂ > citric acid > tartaric acid. It was found that quasi first order rate equation only described the initial stage of Cd²⁺ adsorption suitably, however, apseudo-second order kinetic model was the proper approach for describling the whole process of adsorption. Sum up, the rice straw modified by KMnO₄, KOH and KOH+H₂O₂ could be the potentially valuable adsorbents for absorbing Cd²⁺ in the wastewater solution.