Disclosed are a catalyst electrode for a fuel cell, a method for fabricating the catalyst electrode, and a fuel cell including the catalyst electrode. The presence of an ionomer-ionomer support composite in the catalyst electrode prevents the porous structure of the catalyst electrode from collapsing due to oxidation of a carbon support to avoid an increase in resistance to gas diffusion and can stably secure proton channels. The presence of carbon materials with high conductivity is effective in preventing the electrical conductivity of the electrode from deterioration resulting from the use of a metal oxide in the ionomer-ionomer support composite and is also effective in suppressing collapse of the porous structure of the electrode to prevent an increase in resistance to gas diffusion in the electrode. Based on these effects, the fuel cell exhibits excellent performance characteristics and prevents its performance from deteriorating during continuous operation.