Three water-soluble surfactants based on maleic anhydride-oleic acid adduct (MO) were synthesized. They are triethanol ammonium salt of MO adduct (TEASMO), triethanolamine ester of MO adduct (TEAEMO) and polyoxyalkylated MO adduct (POAMO-23). FTIR and 1 H NMR confirmed chemical structures. The inhibitive efficiency of corrosion on mild steel in 1 M H2SO4 for these surfactants was measured by potentiodynamic technique. The surface and thermodynamic properties of the surfactants were also investigated. The obtained data show that TEASMO exhibit minimum inhibitive efficiency (65%), on the other hand, the obtained maximum inhibitive efficiency was (95%) with POAMO-23. The surface and thermodynamic properties were discussed throughout surfactants chemical structures in relation to corrosion inhibitive effect. (C) 2002 Elsevier Science B.V. All rights reserved.