The inactive biomass of fungus Aspergillus niger O-5 obtained in Cuba was characterized as sorbent of Pb2+ by several structural analysis and others techniques. In addition, the biomass was studied for the separation / preconcentration of Pb2+ from aqueous solution. The maximum biosorption capacity was obtained for the contact time of 30 min and pH 5. The kinetic of sorption process occurred according to the model of Ho. The Freundlich or Langmuir models suitably described the experimental adsorption isotherms. The biomass can be used as sorbent for Pb2+ with a maximum capacity of 4.7 - 6.2 mg g-1. The pretreatment with NaOH solution improved its sorption capacity.