Inhibition and polarization properties of urea, thiourea (TU), acetyl thiourea (AcTu), phenyl thiourea (PhTu), o-tolyl thiourea ( o-tol Tu), m-tolyl thiourea (m-tol Tu), p-tolyl thiourea ( p-tol Tu), 1:3-diphenyl thiourea (di-phTu), 1:3-di- o-tolyl thiourea (di- o tol Tu), 1:3-di-m-tolyl thiourea (di- m-tol Tu) and 1 : 3-di- p-tolyl thiourea (di- p-tol Tu) have been studied in relation to the corrosion of aluminium (1060) in 20% nitric acid. The polarization experiments were carried out using potentiostatic method. The inhibition efficiencies of the inhibitors were determined at 25°, 35° and 45°C and it has been observed that the percentage inhibition efficiencies of the inhibitors increase with increase in temperature. All the inhibitors except urea obey the Langmuir adsorption isotherm below the inhibitor concentration of 300 ppm, but in no case are slopes equal to unity observed. At and above the concentration of 300 ppm, the effectiveness of the compounds decreases, which is attributed to their action as cathodic depolarizers. The inhibitive performance of the compounds is discussed in the light of electronic effects in the thioureas. The potentiostatic anodic polarization curves in the presence of the inhibitors shift towards lower current density region as compared with the curve of the uninhibited solution, but there is no proper correlation between the inhibition efficiencies and the current densities required for the passivation of aluminium.