The olive tree is considered among the most dominant tree crops in Algeria. This culture is often found on the roadsides and around the polluting centers in the western regions. The first study was realized to evaluate the absorp-tion of Copper, Zinc, Lead and Mercury in the roots, shoots and olive leaves irrigated separately with two metallic concentrations (250ppm and 500ppm) was studied in experimental greenhouse. A second study was carried out to determine the presence of metal in olive leaves from the petrochemical in-dustrial zone located in Arzew (Algeria). The results show that Mercury is the most toxic metal for the plant, even at low concentrations. We can see that the contents of Copper, Zinc and Lead in the tissues of the olive tree are pro-portional to their concentrations in the soil. A high concentration of Copper was observed in the leaves than in other tissues. However, Lead was found in the roots and shoots. The elementary composition of the olive leaves of the samples taken in the petrochemical industrial zone shows the absence of dangerous heavy metals such as Lead and Cadmium. This work could con-tribute to clarify the effects of heavy metal in polluted zone on olive trees and its potential toxicity for humans.