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The interaction between zinc and cadmium was studied in tomato leaves (Solanum lycopersicum), in a hydroponic medium. Ten-day-old seedlings were treated with 25 μM CdCl2associated to different concentrations of ZnCl2(10, 50, 100, and 150 μM). We first observed that seven days after the metallic exposure Zn supply clearly reduced Cd concentration in leaves and simultaneously increased Zn uptake. Moreover, the addition of 10 μM ZnCl2relieved the leaves growth inhibition observed under Cd stress. At the same concentration (10 μM), Zn repaired the Cd damages on the membrane lipid content and fatty acids composition. In fact, Zn supplementation at low level (10 μM) restored and enhanced the quantities of the total lipid (TL), galactolipids (GL), phospholipids (PL) and neutral lipids (NL) that were reduced by 25 μM CdCl2. There was also a substantial amelioration in total lipid biosynthesis that was noticeably altered with Cd treatment. In 10 μM Zn-Cd treated leaves the [1-14C]acetate incorporation in total lipids as well as in all lipid classes was similar to that of control leaves. Likewise, levels of tri-unsaturated fatty acids that dropped in total lipids of Cd treated leaves showed an increase after supplementation of 10 μM Zn. Moreover, the beneficial effect of the same dose of Zn (10 μM) on Cd toxicity was confirmed by a significant decrease in the oxidative stress state which was marked by a reduction in thiobarbituric acid-reacting substances (TBARS) levels and a reduction in lipoxygenase (LOX, E.C.1.11.1.7) activity that was significantly enhanced by Cd treatment. These results suggest that 10 μM Zn supplementation proved to be inhibitory for Cd-induced oxidative stress and beneficial for the plant’s survival. However, higher Zn concentrations (50, 100 and 150 μM) and Cd are synergistic in their effect on plant growth parameters and lipid content.