To clarify the mechanism of the response of sugar beet ( L.) to cadmium (Cd) stress, this study investigated changes in the phenotype, physiological indexes, and subcellular structure of under Cd treatment and the transcriptional pattern of the gene (a heavy metal-associated isoprenylated plant protein involved in heavy metal detoxification). The plant height and shoot and root growth of seedlings were inhibited to some extent under 0.5 and 1 mM Cd, with gradually wilting and yellowing of leaves and dark brown roots. When the Cd concentration was increased, malondialdehyde content and the activities of peroxidase, superoxide dismutase, and glutathione S-transferase increased differentially. qPCR indicated that the expression of was induced by different concentrations of Cd. Although transmission electron microscopy revealed damage to nuclei, mitochondria, and chloroplasts, exhibited strong adaptability to 0.5 mM Cd according to a comprehensive analysis using the membership function. The results showed that may reduce cell damage and improve its Cd tolerance by regulating functional gene expression and antioxidant enzymes. This study increases our understanding of the Cd-tolerance mechanism of and provides insights into the use of in Cd bioremediation.