Abstract: In order to achieve cleanup and remediation of arsenic (As) and cadmium (Cd) co-contaminated paddies, field experiments were carried out to extract As and Cd with rice plants under the application of soluble organic fertilizer. In order to evaluate the effect of soluble organic fertilizer and the extraction efficiency with rice plants, the diffusion gradient in thin film technology (DGT) was used to in situ monitor the dynamic profile As and Cd at tillering, heading and flowering, and grain filling stages. At harvest, the changes in soil As and Cd fractions were revealed by sequential extraction, and As and Cd accumulation in rice tissues were determined. To highlight the importance of root removal, the differences in soil As and Cd concentrations between treatments with rice roots retained and removed were analyzed. The results showed that the application of soluble organic fertilizer (OF) promoted soil As and Cd dissolution and release. For example, relative to the control, the average concentration of soil DGT-As and DGT-Cd increased by 34.2% and 54.9%, respectively, after 39 days of treatment. The total As and Cd extracted by each single rice plant were 12.63 and 1.18 mg, respectively, with 97.6% and 81.3% of total As and Cd sequestered in the roots. Removal of rice roots at harvest reduced total soil As and Cd concentration by 5% and 10%, and soil profile of DGT-As and Cd showed 41.9% and 56.4% decrease on average compared with the treatment with roots retained in soils. In addition, the readily available As (F1+F2) and Cd (F1+F2) in the post-treated soils with rice root removed decreased by 9.8% and 6.1%, respectively. Based on the present results, the application of soluble organic fertilizer can promote soil As and Cd dissolution, which could enhance bioavailable As and Cd depletion by rice extraction and root removal from paddy soils. This provides a useful way for cleanup and safe utilization of paddy soils with As and Cd co-contamination.