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In a preliminary study, the winter farmland weed cleavers (Galium aparine) was found to have the characteristics of a cadmium (Cd) accumulator. In this study, pot and field experiments were conducted to confirm this. In the pot experiment, the biomass, resistance index, plant height, branch number, tolerance index and root length of cleavers decreased, while the root/shoot ratio increased with increasing Cd concentration in the soil. The Cd contents in the roots and shoots of cleavers increased with increasing Cd concentration in the soil. The Cd content in shoots reached 139.63 mg kg-1 at a soil Cd concentration of 75 mg kg-1, which exceeded the critical value for a Cdhyper- accumulator (100 mg kg-1). The maximal Cd content and extraction in shoots were 184.43 mg kg-1 and 32.46 pg plant-1, respectively, at 100 mg kg-1 Cd in the soil. The shoot bio-concentration factor of cleavers were greater than 1.0, while the translocation factor was less than 1.0 for all treatments. In the field experiment, the total Cd extraction in cleavers' shoots was 2.81-3.69 mg m-2 at soil Cd levels of 2.04-2.89 mg kg-1. Therefore, cleavers is a Cd-accumulator that could be used to remediate Cd-contaminated farmland soil. [ABSTRACT FROM AUTHOR]