The impacts of corrosion are frequent and occur in various activities. There are several ways of combating impacts, among them the use of surfactants have been targeted as corrosion inhibitors, because they form protective films on anodic and cathodic areas. Although they areeffective in the corrosion control, some surfactants have high cost andare toxic to the environment, making its use questionable. In order to fulfill the growing demand for sustainable corrosion inhibitors, the objective of the present workwas to perform a research about the inhibitory action of a hydro-alcoholic extract from vegetal specie OurateaParviflora. The extract was evaluated in free formand in a micro-emulsified system with seven different concentrations regarding the corrosion inhibition efficiency into a saline medium (NaCl 3.5%). Was used the method Linear Polarization Resistance method, also determining the behavior and the isotherm of the metal/inhibitor adsorption process. According to the obtained results, the maximum inhibition efficiencies were observed at 67.70% (12.5 ppm), 77.94% (200 ppm) and 85.66% (200 ppm) to the free hydro-alcoholic extract, saline micro-emulsified system (SME-S) and saline micro-emulsified system with extract (SME-S-EB), respectively. The micro-emulsified system SME-S presented the maximum efficiency in the concentration 200 ppm, however after the extract addition, the efficiency reached a value of 81.86% the 25 ppm. In addition, all the experimental data from the adsorption process fitted the Langmuir isotherm. According to the data calculated from Gibbs free energy, it was detected a spontaneity of the adsorbent inhibitors on the steel surface, suggesting that the film formation occurs by physical adsorption of the inhibitor on metal surface. The study of the synthesis of inhibitors under the sustainability bias confirmed that these new formulations can be considered as sustainable because they use biodegradable products and renewable resources as raw materials. The results showed that the systems can be used as alternative sources in the formulation of corrosion inhibitors.