Catalytic electrodes, and their production process, as well as electrochemical devices and their fabrication process are provided. The catalytic electrode includes a catalyst layer, which contains an electrolyte composed of a solid polymer such as polytetrafluoroethylene and also contains catalyst particles such as Pt. The solid polymer electrolyte has a crosslinked structure. The catalytic electrode is produced by forming the catalyst layer with the solid polymer and catalyst contained therein, and exposing the catalyst layer to radiation to crosslink the solid polymer and to bond side chains to the solid polymer, and further to introduce into the side chains ion dissociative groups.