The potential for arsenite removal using plant-microbial fuel cells (PMFC) was evaluated. In such a system, O2 is excreted by living rice plant roots and Fe(II) play important roles in initiating Fenton reactions. Fenton reagents, including H2O2, Fe(II), were generated in-situ without an electricity supply. The HO· produced in the Fenton reaction were capable of oxidizing arsenite apparently and efficiently. The results might provide a new insight for As(III) oxidation in rice rhizosphere.