Biosorption is the ability of biological materials to absorb/adsorb heavy metals from waste water. The major advantages of biosorption over the conventional treatment method includes low cost, high efficiency, minimization of chemicals in sludge, no additional nutrient requirement, regeneration of biosorption and possibility of metal recovery. With regard to this, the objective of the study was to examine the possible role of the functional groups on biomass of Rhizopus stolonifer for removal of lead from water. The role of amines and carboxylic groups in the lead adsorption was studied. Result indicates that carboxylic groups are more efficient in removal of lead as compared to amino groups as indicated by percent reduction in the sorption efficiency of biomass ,after modification of functional groups. Sorption efficiency of the said functional groups was confirmed further by observation of biomass after sorption studies under an inverted microscope.