The chemical and interfacial properties of two bitumens were compared. The chemical properties were characterized by determining the asphaltene and resin contents of the bitumens. The interfacial properties were studied by wettability measurements and by determining the zeta potential of bitumen dispersions in acid water, with and without maturation of asphaltene dispersions in acid water and of bitumen dispersions in acid water containing asphaltenes. The study of the influence of the maturation at 80 degrees C for 7 h and of the addition of asphaltenes on the stability of the bitumen dispersion showed that the evolution of the interfacial properties of the bitumen depends on the resin content of the bitumen.