Point of present exploration was to figure out the anticorrosion activity of Acacia Cyanophylla (Saligna leaves) extract on the corrosion of mild steel in dilute sulfuric acid medium, using weight loss measurements and electrochemical impedance spectroscopy. The result of the study revealed that the extract act as a potent inhibitor on mild steel in acid medium. The increase in inhibitor concentration and immersion time showed a positive effect on inhibition efficiency. EIS exhibited one capacitive loop which indicates that the corrosion reaction is controlled by charge transfer process. The increase of phase shift (n) in presence of (ACLE) lower surface roughness. This change reveals the adsorption of the inhibitor compound on the steel surface. According to the results of weight loss measurements, the adsorption of the extract on the steel surface can be described by the Langmuir isotherm. The inhibition mechanism of (ACLE) molecules involves physical interaction between the inhibitor and metal surface. Additionally, Protective film formation against acid attack was confirmed by FT-IR and AFM techniques.