Inorganic filler materials are often incorporated into polymer membranes to improve their mechanical, thermal and chemical stabilities. In case of proton-conducting polymers, however, it is necessary to support or at least not to disturb the proton-conducting matrix. By suitable combination of polymer and filler, effective and highly conductive composite membranes can be prepared. This article gives an overview of the possible applications of a special kind of such proton-conducting composite membranes containing functionalized SiO(2) particles with ordered mesoporosity in fuel cell, in desalination and in photocatalysis.