Black nightshade was used as a test material to study the effects of chelating agents and plant growth regulators on Cd accumulation in black nightshade and its response mechanism. Pot experiments were used to study iminodisuccinic acid and 28-epigenolide and the effects of BR alone and in combination application on Cd accumulation and antioxidant system and soil enzyme activities in black nightshade. The results showed: with the increase in iminodisuccinic acid concentration, the growth inhibition of black nightshade was stronger, and the content of weak acid and reducible Cd in soil increased, while 28-epigalassinolide could alleviate the stress effect of iminodisuccinic acid on the growth of black nightshade; Iminodisuccinic acid decreased the activities of CAT and SOD and increased the activity of POD in leaves of black nightshade, while 28-epigalassinolide could alleviate the oxidative stress effect of black nightshade; With the increase of iminodisuccinic acid concentration, soil catalase activities and sucrase activities decreased, while urease activities increased, while 28-epigenolide could increase soil catalase activities and sucrase activities; Treatment with 5 mmol/L iminodisuccinic acid and 0.02 mg/L 28-epicolinolide could increase the accumulation of Cd in the shoot of black nightshade, which was an effective measure for remediation of Cd contaminated soil.