The invention relates to carbon-nanotube-loaded platinum-iron superlattice alloy nanoparticles used for an oxygen reduction reaction of a proton film fuel cell negative electrode, and a preparation method for the nanoparticles. Chloroplatinic acid and ferrous nitrate are used as a precursor; carbon-nanotube-loaded platinum-iron alloy nanoparticles are obtained by adopting a sodium borohydride reduction method implemented in an ethylene glycol solution; then the carbon-nanotube-loaded alloy nanoparticles are subjected to thermal annealing processing in an inert gas atmosphere to convert the carbon-nanotube-loaded alloy nanoparticles into the carbon-nanotube-loaded platinum-iron superlattice alloy nanoparticles. The method is simple in process, safe in operation, free of reduction gas in the thermal annealing process, and high in controllability; and the activity and the stability of the catalyst oxidization reduction reaction of the obtained product catalyst are both improved at a relative high degree.