We studied the capability of various kinds of sulfonate-based electrolytes to form a bilayered Al2O3/polypyrrole (PPy) film on an aluminum substrate in aqueous solution. As electrolytes, we selected sodium p-toluenesulfonate (monovalent sulfonate), sodium naphthalene-trisulfonate (trivalent sulfonate), poly(sodium 4-styrenesulfonate) poly(sodium vinylsulfonate) (sulfonate polymer), sodium n-dodecylbenzenesulfonate (SDBS), sodium. butylnaphthalenesulfonate(BNS), and sodium n-dodecylsulfate (SDS, surfactant sulfonate/sulfate). Among the sulfonates we investigated, SDBS, BNS and SDS appeared to form a barrier-type Al2O3 layer with high coulombic efficiency in the absence of pyrrole. In the presence of pyrrole, anodization of these electrolytes resulted in the formation of Al2O3 and PPy layers, simultaneously.