Abstract: To study the effect of iron-based compound soil conditioner on soil pH value, soil available Cd content, and yield and Cd content of rice in different polluted soil types, the mechanism of iron- based compound soil conditioner to reduce soil Cd bioavailability was discussed. In this paper, acid, weak acid and neutral Cd polluted soil were selected, with 2250 kg/hm2 application rate of iron- based compound soil conditioner for field plot test. The results showed that the iron-based compound soil conditioner could increase soil pH value, reduced soil available Cd content and the bioavailability coefficient of Cd. The iron-based compound soil conditioner had the best Cd reducing effect on the neutral paddy soil in Zhuzhou. The soil conditioner could also improve the yield of brown rice and reduce Cd content in brown rice. The content of Cd in brown rice of Zhuzhou and Xiangtan reached the national food hygiene standard. The results could provide a theoretical basis and data support for the treatment of cadmium contaminated soil and safe production of rice.