Lead (Pb) is one of the highly persistent and major toxic health hazard listed by various health organizations. A stable, specific, and simple sensor which can rapidly detect the Pb in drinking water is required urgently. To this end, we have prepared stable and uniformly sized colloidal silver nanoparticles (AgNPs) using citric acid for the color-based sensing of Pb in water samples. The synthesized AgNPs are characterized by UV-Vis spectroscopy, DLS-Zeta, and TEM to access their optical and morphological properties. The cit-AgNPs have shown a great affinity/selectivity towards lead (Pb) over Cd, Mn, Cr, Fe, Co, Pb, Hg, Zn, and Ti ions. Thus, based on the interaction of cit-AgNPs and Pb, a colorimetric sensor for selective, specific, and expeditious detection of lead metal ions has been developed.