Metal salts of mono(hydroxypentyl)phthalate [M(HPP),, where M is Ca2+, Cd2+, Pb2+, or Zn2+] were synthesized by the reaction of 1,5-pentane diol, phthalic anhydride, and metal acetate. A new series of metal-containing polyurethanes containing ionic links in the main chain were synthesized by the reaction of hexamethylene diisocyanate or toluylene 2,4-diisocyanate with the M(HPP)2 salts. The structures of the monomers and polymers were confirmed with infrared, H-1-NMR, and C-13-NMR spectra and elemental analysis. The polymers were also characterized with thermogravimetric analysis, differential scanning calorimetry, and solubility and viscosity measurements. The antibacterial activity of these polyurethanes was investigated with the agar diffusion method.