Silver ion oxidation process was studied in different biological molecules by Density Functional Theory; this by using the Becke three parameter Lee, Yang, and Parr functional and the Pople 6-31G (d) and Los Alamos LANL2DZ basis sets. The calculation was used to find the lowest energy molecular structure, molecular orbitals, and chemical reactivity parameters. Chemical hardness showed that the oxidation process begins in the purine and pyrimidine bases. The frontier orbitals electronic density distribution were analyzed in the biological molecule-silver ion complex. This distribution clearly revealed the transfer of electrons from highest occupied molecular orbital to lowest unoccupied molecular orbital indicating an oxidation process.