The objective of this study was to evaluate the use of activated carbon obtained from orange peel (Citrus sinensis) in the removal of Pb (II) ions present in the waters of the Anticona-Cerro de Pasco River.Activated carbon with phosphoric acid was prepared as an activating agent in an impregnation ratio of 0.70 g H 3 PO 4 per gram of material.The physicochemical properties of the adsorbent were studied using the isothermal adsorption of nitrogen (BET), electron microscopy (SEM) and infrared spectrophotometry with Fourier transform (FTIR).The most influential factors in the adsorption process were the pH of the solution, contact time, porous structure and acidity of the carbon.The results indicate that Freundlich's model is the one that best adjusts the experimental data, reaching a bioadsorption capacity of 478.5 mgL-1 Pb (II), which represents 95.70% lead removal (II). Keyword-Adsorption, bio-carbon, Freundlich's isothermal. I. INTRODUCTION Contamination of drinking water sources by pathogens, toxic inorganic organisms, radionuclides and synthetic and emerging organic pollutants is a public health concern; the presence of heavy metals being one of the greatest, due to inadequate treatment of wastewater discharged into water bodies and containing heavy metals such as lead, chromium, cadmium, cobalt and zinc,which are toxic to living organisms and which due to their physicochemical properties are not biodegradable [1]-[3]. In this context, the exploitation of mineral resources has been considered an essential activity for the development of countries such as Peru, highlighting the production of lead, which has increased over the years, consolidating itself as one of the most important producers of lead in the world [4]. However, it has brought with it a series of negative effects on the environment, causing profound changes, with the consequent deterioration of landscapes, plants, water [5]. The central region of Peru is among the most affected with this environmental problem, the presence of lead in the upper zone (Cerro de Pasco) and average of the Mantaro River basin is variable, evidenced in the source of the Mantaro River values that exceed the LBC-PMR = 0.0210 mg L-1 , being the stations of greatest concern San Juan = 0.049 mg L-1 , Anticona River = 0.630 mg L-1 , before discharge to Mantaro, where it exceeds between 2.3 and 30 times respectively the LBC-PMR, and 196.9 and 15.3 times the standard proposed by CONAMA-Chile class a1 (0.0032 mg L-1) respectively.It is important to note that the concentration of lead in the Anticona River exceeds 6.3 times the class III standard of the General Water Law-LGA [6]. Thus, a variety of technologies have been adopted for the removal of heavy metals in wastewater, such as chemical oxidation, precipitation, adsorption, ion exchange, reverse osmosis and membrane separation.Adsorption is the process in which molecules are concentrated in an interfacial layer and are considered an effective remediation strategy due to the low cost and regeneration of adsorbent, high selecti...