The introduction of polymers to reservoir is a common technique for enhanced oil recovery. In this paper, the combination of electrochemical measurements, surface analysis and rheological measurements was employed to elucidate impact of hydrolysed polyacrylamide (HPAM) on corrosion behaviour of carbon steel. The interaction between HPAM and inhibitor was also studied for first time. Adsorption isotherm analysis and XPS implied that corrosion inhibition properties of HPAM are due to chemisorption of polymer on carbon steel surface. Introduction of inhibitor in system resulted in increased viscosity and corrosion inhibition at 25 and 75 °C due to H bonding between HPAM and inhibitor.