Polysulfone ultrafiltration hollow fibres are modified on the surface with polymers obtained by polycondensation of dimethylolurea (DMU). Depending upon the reaction conditions, polymers on the surface present a gel or a film form. In the first case the membranes are called "gel-supported" and in the second case "coated." Modified and unmodified polysulfone membranes were analysed by XPS spectroscopy. The modifications observed on a modified membrane were studied by reference to the previous article dealing with XPS analysis of gel and film DMU polymers. The study showed that gel-supported membranes are modified by a polymer of a gel-type chemical structure whereas coated membranes are modified by a polymer of film-type chemical structure. The nature of the support, polysulfone, does not affect the final form of the polymer.