A pot experiment was conducted with three levels of biochar addition (0, 2.5% and 5% (w/w)), to investigate the effect of biochar on the uptake of Cd and Pb by ratoon rice (Oryza sativa L.). The results indicated that biochar addition decreased the accumulation of Cd and Pb both in the main crop and ratoon crop. This could attribute to the following reasons:Biochar addition increased the soil pH and the content of soil organic matter, which consequently promoted Cd and Pb transformation from acid soluble fraction to reducible fraction. The CaCl₂-extraction Cd and Pb concentrations were also reduced in soil, resulting in the decreased uptake of Cd and Pb by rice root. Biochar addition decreased the transfer factors (TF) of Cd from leaf to brown rice both at main crop and ratoon crop, and also reduced the TF_stem-leaf and TF_stem-rice of Pb; therefore, the concentrations of Cd and Pb in brown rice were decreased. The Cd content in brown rice was 0.15 mg/kg inratoon crop with 5% biochar addition, which was below the hygienic standard for rice in China (0.2 mg/kg). And 5% biochar addition reduced Pb concentration in brown rice of ratoon crop by 68.18% compared with the control. What is more, this research also found that Cd and Pb concentrations in brown rice of ratoon crop were lower than those in the main crop. In a word, biochar addition could reduce the Cd and Pb transfer from soil to ratoon rice.