Metal pipelines and other components in the oil field are frequently exposed to chemicals that might cause corrosion, especially when the metal and chemicals are in a solution, such as down hole fluids. Inhibitors are one of the very important industrial additives that are commonly used in Iraqi petroleum industry to decrease the corrosion that cause damage to pipelines ,water and waste water system. from her came the urgent need to prepare corrosion inhibitor material one of the most important properties of these compounds act as surfactants working to remove or reduce the surface tension between the two immiscible phases with each other and make it easier to mix. In this research was to prepare three types of corrosion inhibitors by using fatty acids and converted them into the fatty alkyl halides with presence of hydrochloric acid and react later with some tertiary amine in various mole ratios, and then identified by classical methods melting point measurement , solubility test and [FTIR, 1H-NMR and 13C-NMR] . Morphology of the carbon steel was examined using scanning electron microscopy (SEM) in presence and absence of inhibitor. in the last step assessment the inhibitors of low carbon steel in acidic medium as case study by using potentiostat device and weight loss to calculate the corrosion rate and inhibition efficiency. The result were as follow P1 are 81.30% ., P2 are 81.79% , P3 are 97.56%.