When it comes to the environmental pollution of heavy metals, it's necessary to say that this has drawn the attention of numerous research groups all over the world. When it comes to the contamination with heavy metals, it's also notable that this has increased the cocnern of citizens. The reason to this is their toxicity in relation to low concentrations, the fact that they are not biodegradable and they are not prone to bioaccumulation. Increasing demand for the recovery of these metals from industrial wastewater emphasized the development and testing of new materials, including the use of heavy waste biomaterials. For the last three to four decades, the biopolymers are intensively studied because of their interaction with metal ions. Cellulose, chitin and chitosan are commonly studied biopolymers for sorption of metal ions. It's important to mention that chitin is contained in the skeleton of the custaceans, in fact, it's their main ingredient (eg, crab, shrimp, insects and shrimp) and cell walls of fungi. Chitin is a polymer composed of acetilglucosamine units. In the case of some Mucorales species, chitin is replaed by chitosan, a polymer composed of glucosamine units. Chitosan is commercially produced deacetylation of chitin and a typical biopolymer with excellent input of metal ions. The metal cations may be adsorbed on the chelating amino and hydroxyl groups of chitosan in near neutral solutions. In the case of metal anions, sorption is done by electrostatic attraction to the protonated amine groups in acidic solutions. However, the presence of the ligand and the pH highly regulate the sorption performance and input. In this article we will talk about examples with heavy metals such as Cu, Zn, Cr and toxic metals such as Pb, Hg.