The inhibitive action of extract of Telfariaoccidentalisleaves as corrosion inhibitor for mild steel in H2SO4 solutions was investigated using conventional weight loss, electrochemical polarizations and electrochemical impedance spectroscopy. The results showed that the extract of Telfariaoccidentalisleavesperformed well as inhibitor for the corrosion of steel in sulphuric acid media. Inhibition efficiencies increased with increasing concentration of the plant extract but decreased with the temperature rise. Both the cathodic hydrogen evolution and the anodic dissolution of mild steel was inhibited, hence the active molecule of the extract studied acted as a mixed type corrosion inhibitor.