The corrosion rate and potential of lead were measured in 0.2—2M NaOH Solutions con- taining 10“4-5 x 10_,M Na2MoO4. Results showed that the corrosion rate and potential dccrease with increase of molyhdate concentration. This indîcated the deceleration of the cathodic reaction. Anodic polarisation showed that the increase of MoO4“2 concentration delays the onset of passivity. Cathodic polarisation curves were also measured; the results confirmed the deceleration of the cathodic reaction with increase of molyhdate concentration.