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The willow (Salix spp.) is a promising candidate coping with global climate warming and environment pollution. In this study, differences in plant growth, Cd uptake and accumulation, and extractable Cd in the rhizosphere between flooded and non-flooded (well-drained) Salix genotypes were investigated using a pot experiment in the rainshelt. All Salix genotypes grew well under well-drained conditions. In contrast, the flooded Salix genotypes developed hypertrophied lenticels, adventitious roots and aerenchyma, and decreased aboveground biomass production compared with the corresponding non-flooded genotypes, varying with genotypes and Cd levels in the medium. The non-flooded Salix genotypes had high Cd accumulation in aerial tissues with high leaf Cd bioconcentration factors (BCF) and translocation factors (TFs) relative to genotypes, displaying good Cd phytoextraction potentials. The flooded Salix genotypes dramatically decreased Cd accumulation in aerial tissues with low Cd BCFs and TFs, and large amounts of Cd accumulated in roots compared to the non-flooded genotypes, showing Cd phytostabilization traits. The extractable Cd in rhizosphere changed with genotypes and treatments, and comparatively, EDTA-extractable Cd could reflect well Cd phytoavailability to the willows in the soil. It was concluded that flooding tended to shift from phytoextraction to phytostabilization for Cd by willows during whole growing season.