Gold Nanoparticles exhibit intrinsic surface reactivity and high surface areas and can strongly chemisorb Mercury, Lead and Cadmium. The size, surface structure and interparticle interaction of nanomaterials determine their unique properties and the improved performances and make their potential application in many areas. Monitoring the levels of Hg , Pb, Cd along with Malathion and Chloropyrifos pesticides using Gold Nanoparticles is a continuous research and it is necessary to detect the concentration levels of Hg, Pb, Cd and Malathion, Chloropyrifos pesticide residues in various environmental samples upto PPb levels following analytical techniques. Further Gold Nanoparticles will be used for monitoring the levels of Hg, Cd, Pb, and other pesticide residues in various environmental samples. In future, this project will become the basis for monitoring the levels of Heavy metals and pesticide residues present in various environmental, biological and pharmaceutical samples.