The effect of CrO42-, MoO42- and WO42- anions on the inhibition of aluminium corrosion in 0.5 M NaCl solution was investigated. The study comprised potentiodynamic polarization, potentiostatic current-time measurements complemented by SEM-EDAX and XPS investigations. It was found that, the pitting potential of an Al electrode in 0.5 M NaCl solution shifts in the positive direction by addition of CrO42-, MoO42- and WO42-anions, and the shift in potential increases with increase in concentration. A pronounced inhibiting influence was achieved on addition of CrO42-, MoO42- and WO42- anions to the electrolyte during potentiostatic current-time measurements. Chromate anions exhibit a great passivating influence during I/t measurements. This can be explained by the fact that the chromate anion, as a powerful oxidizing agent, is capable of oxidizing the corrosion sites to give a stable Al2O3 film. The inhibition observed on addition of molybdate anions is attributed to the adsorption and reaction of MoO42- anions on the electrode surface forming a molybdate layer which selectively impedes the ingress of Cl- ions and hence inhibits the pitting attack. The adsorption of WO42- anions at flawed areas and developing pits was found to be the main factor for the observed inhibition.