Our study focuses on the effect of heavy metals (case of Cu) on the plant of Atriplex halimus grown in hydroponic conditions. The objective of this study is to analyze a number of enzymatic systems of the plant in response to stresses caused by copper (as CuSO4). The analyses include enzyme profiles, protein content and chlorophyll content in A. halimus leaves. The plant was subjected to different concentrations of CuSO4 (50, 500, 1000 and 2000 µM). The samples were taken for analysis after 6, 24 and 48 hours. The results show that the chlorophyll content decreases significantly with the increase of the Cu dose, and conversely the protein content undergoes a slight decrease after 6h (38%) at 2000 µM Cu, then an increase up to 155% at 500 µM after 48h. Non-denaturing gel electrophoresis (PAGE) revealed three CAT isoforms, three SOD isoforms and five POX isoforms. One new SOD isoform and two new CAT isoforms compared to the control were found following Cu treatment. The band density of these three enzymes increased with Cu.