<p>To ensure the safe cultivation of <i>Brassica parachinensis</i>, the Cd accumulation trait of Cd pollution-safe cultivar (Cd-PSC), SJ19, was evaluated by comparison with the high-Cd-accumulation cultivar, CX4, under hydroponic condition with gradient Cd treatments. Shoot Cd concentrations in SJ19 were higher than those in CX4 shoots under high Cd concentration (3.0&#xa0;mg/L), contrary to its low-Cd-accumulation observed under low Cd treatments (0.5 and 1.0&#xa0;mg/L). Meanwhile, no differences in root and xylem sap Cd concentrations were observed between SJ19 and CX4 under 3.0&#xa0;mg/L treatment, which allowed higher Cd transportation capacity in SJ19 under high Cd conditions. Additionally, an elevation in phytochelatins (PCs) concentrations was observed in both cultivars as the duration of exposure to 3.0&#xa0;mg/L Cd increased. PCs profiles varied in shoots and roots, with low-molecular-weight PC₂ being predominant in shoots and high-molecular-weight PC₄ dominating in roots. Simultaneously, PCs related to Cd detoxification and root-to-shoot transportation were higher in SJ19 roots than those in CX4 roots. Furthermore, the PC₄ concentration was linearly correlated with Cd concentration in roots of both cultivars and was higher in SJ19 than that in CX4 under high Cd treatment, thus confirming that PC₄ was the key PCs for cultivar-dependent Cd accumulation trait of <i>B. parachinensis</i>. Our results revealed that PCs biosynthesis was the dominant strategy to cope with Cd stress in <i>B. parachinensis</i>, and Cd accumulation trait of Cd-PSC was reversed via high Cd induction and PCs mediation.</p> Graphical Abstract <p></p>