A terpolymer resin derived from Resorcinol, Formaldehyde and Salicylic acid was synthesized through condensation reaction. Transition metal ions namely Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) were incorporated into the resin forming polymer-metal complexes. Both the resin and the complexes were characterized by FTIR, UV–Vis., XRD, 1H NMR, TGA and SEM/EDX. Elemental analysis was carried out to determine the percentage of different elements present in the resin and its complexes. Conductivity measurement data showed higher conductivity of the metal complexes as compared to its precursor resin. The terpolymer resin and its metal complexes were tested against five strains of gram positive bacteria namely; S. aureus, S. mutans, S. pyrogenes, C. xerosis, C. diphtheria, and three strains of gram negative bacteria namely; E. coli, K. pneuomoniae and P. aeruginosa. All the metal complexes exhibited enhanced antibacterial properties as compared to its terpolymer resin. The Mn(II) and Co(II) demonstrated strong antibacterial activity.