In the drive towards clean and sustainable energy, researching for efficient and stable electrocatalysts with high utilization efficiency of noble metals for fuel cells remains a forbidden challenge. To this end, we herein report a facile approach to synthesize the trimetallic Au-decorated PdRu nanopopcorns enclosed with abundant surface protuberances and Au-rich surface. These features thereby endow them with unprecedented electrocatalytic activity towards liquid fuel oxidation in the alkaline media. The mass/specific activities for Au-decorated PdRu nanopopcorns are calculated to be 4712.2 mA mg(-1) and 22.1 mA cm(-2), 5.8 and 2.8 times higher than that of commercial Pd/C. More importantly, they are also stable in the alkaline media with less activity decay for successive cyclic voltammetry of 500 cycles. Both the enhanced activity and durability can be attributed to the popcorn-like nanostructure together with the electronic and synergistic effect evolved from Pd, Au and Ru. This work opens the possibilities for the rational design of trimetallic or polymetallic nanocatalysts with attractive structure, which may lead to the enormous development of fuel cells and beyond.