The properties and aging of biochar are important factors affecting the remediation effect of biochar in immobilizing Cd-contaminated soil. The differences of Cd²⁺ adsorption and Cd-contaminated soil immobilization efficiency of four different types biochar materials (sludge-based, straw-based, animal and poultry manure-based and wood-based) were comparatively investigated. The results showed that the application of biochar significantly increased the pH of soil pore-water (except palm fibers biochar), and decreased the concentrations of DOC and Cd in pore-water, and thus reduced the Cd uptake of rice roots in pore-water. At the same time, the application of four kinds of biochar increased soil pH value, but decreased soil available Cd, rice root and grain Cd content. However, aging weakened the immobilization effect of rice straw biochar and significantly enhanced the immobilization effect of palm fibers biochar on soil Cd, while aging had little effect on ash rich pig manure biochar and sludge biochar. Therefore, the raw materials and aging effects of biochar must be considered when choosing biochar immobilization to remediate Cd contaminated paddy soil.