Abstract: A study has been undertaken to investigate the response of Amorpha fruiticosa to drought stress under different paclobutrazol applications. Physiological parameters, including peroxidase (POD) activity, the contents of malondialdehyde (MDA), soluble protein, soluble sugar and chlorophyll, and the ability of leaves to conserve water, were measured using pot experiments with six levels of paclobutrazol application (0, 10, 50, 100, 150 and 200 mg/L, represented by D₀, D₁, D₂, D₃, D₄ and D₅ respectively). Drought resistance was investigated using subordinate function analysis. With increasing drought stress, POD activity, MDA content and the rate of leaf water loss increased while soluble protein content decreased. Chlorophyll content increased except under D₀ and soluble sugar content increased overall. Under mild and severe drought stress, POD activity under D₅ was highest, MDA contents under D₂ and D₃ were lowest, and the contents of soluble protein, chlorophyll, soluble sugar and leaf water conservation ability under D₄ were greatest. The order of drought resistance was D₄>D₅>D₃>D₂>D₁>D₀, suggesting that the resistance of A. fruiticosa is elevated by paclobutrazol application and that D₄ is the optimum application level. Grey correlation analysis showed that soluble protein, chlorophyll and soluble sugar were closely correlated with drought resistance under paclobutrazol application, suggesting that they could be key indicators in evaluating resistance under such applications. This study provides references for the utilization of paclobutrazol applications for rock slope protection with plantings of A. fruiticosa.