Recently, the use of selenium (Se) to alleviate the toxicity of cadmium (Cd) in living organisms has attracted increased attention. Studies have shown that Se can reduce the uptake of Cd by rice (Saidi et al. 2014, Liao et al. 2016). However, most studies have only focused on the antioxidant function of Se, Se-regulated photosynthetic system and Se repairing damaged cells, while research on how the Se inhibits Cd uptake and transfer in rice roots has not yet been systematically conducted.