Jatropha curcas is a tolerant and accumulator plant of heavy metals (HMs). Little is known about the mechanisms behind this ability. It is suggested that antioxidant enzymes might participate; however, there are no studies reporting the relationship between the activities of antioxidant enzymes and the presence of HMs in an in vitro cell suspension culture of J. curcas. The aim of this study was to determine the effect of chromium (Cr) or lead (Pb) at 0.0 to 3.0 mM on the activity of three antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX) through the growthofcellsuspensioncultures(CSC)ofJ.curcas. Theactivitydisplayedbythoseenzymeswasstatisticallysignificant (P≤0.05) when Cr or Pb was used. The greatest enzymatic activity was noted at the first hour of culture for SOD and at five h for POX and CAT. After 192 h, the activity of these three enzymes decreased, which coincided with the exponential growth phase of the cell culture. The results indicated that there is a close relationship between the presence of Cr and Pb and SOD, CAT, and POX activities in a cell suspension culture of J. curcas, which can explain the plant’s capability for tolerating and accumulating high concentrations of Cr and Pb