The corrosion inhibition of mild steel in 1 M H₂SO₄ solution by Microdesmis puberula root extract has been studied using weight loss and hydrogen evolution methods. The data obtained revealed that the inhibition efficiency increased with increase in extract concentration up to 4 g/L, before decreasing at 5 g/L. An increase in temperature led to a decrease in the inhibition efficiency by the extract. The adsorption of Microdesmis puberula root extract on mild steel surface obeyed Freundlich adsorption isotherm and occurred spontaneously. Physical adsorption has been proposed for the adsorption of Microdesmis puberula root extract on mild steel surface. The activation energy and other thermodynamic parameters for the inhibition process have been calculated and discussed.