Abstract: This study investigated the effects of exogenous silicon on the growth and cadmium(Cd)resistance of tomato seedlings through hydroponic experiments.A hydroponic method was employed with experimental designs involving different concentrations of cadmium and silicon.The dry weight and fresh weight of the plants were measured,and the cadmium accumulation in the roots,stems,and leaves of tomato seedlings was determined using inductively coupled plasma mass spectrometry(ICP-MS) to assess the migration and distribution of cadmium.The results suggested that the addition of 0.5 mmol/L and 2 mmol/L silicon both promoted the growth of tomato seedlings under cadmium stress,reduced cadmium content,and regulated cadmium accumulation.Among them,the 2 mmol/L silicon treatment exhibited the best effect,with cadmium content decreasing by 67.7%,67.3%,and 66.7% in the roots,stems,and leaves,respectively.The total cadmium accumulation in tomatoes decreased by 68.4%.These results indicate that exogenous silicon can enhance tomato's resistance to heavy metal stress by regulating cadmium uptake and distribution.