A new polymer based on tartrate-ethylene diamine phosphonic acid (TEDPA) was synthesised and its complex with metal ions were characterised. Electrochemical and weight change measurements were carried out to study the corrosion inhibition property of this polymer for mild steel in 60 ppm chloride solutions. Spectrochemical analyses of the inhibited surface film were also done. This polymer when used alone, accelerated corrosion but offered good inhibition in the presence of zinc ions. Detailed mechanism of corrosion inhibition is discussed.