Phytoremediation is a biotechnology using plant species to decontaminate various substrates. Whatever the process, the cost is generally lower than conventional treatments and the method better for the protection of ecosystems. The different techniques depend on the contaminated medium (atmosphere, water, soil) and the type of pollutant. Pollutants can be organic molecules generated by human activities such as pesticides, hydrocarbons, chlorated or halogenated solvents, and explosives. Pollutants can be also inorganic molecules, i.e. metallic trace elements (IVITE), which are released in the environment as a result of human activities (essentially mines and various pesticides) or natural pollutions (volcanism, erosion, leaching).This review presents the different processes of phytoremediation and more particularly phytoaccumulation of MTE and emergence of woody species for this biotechnology.