The corrosion inhibition effect of Cocos nucifera (CN) surfactant inhibitor, has been inspected on 316L steel in 5 M HCl and H2SO4 solutions by weight loss (WL) method. The results revealed that the presence of alkanols, glycosides, steroids and terpenoids in CN surfactant supported the inhibitor by retarding corrosion effect to give an optimum inhibition efficiency of 93.71% in HCl and 89.66% in H2SO4 solutions after 504 h. Also, the regression values for both acidic solutions were close to unity after obeying Langmuir isotherm adsorption mechanism with 0.9971 for HCl and 0.9882 for H2SO4 solution. The result confirms that CN surfactant inhibitor performed better in HCl solution than in H2SO4 solution. Keywords: Corrosion inhibitor; active components; austenitic 316L material; weight loss method; adsorption isotherm.