Anodic aluminum oxide membranes with serrated nanochannels have been successfully fabricated via a two-step annodization method. The serrated channels with periodic intervals are aligned at an angle of 25° along the stem channels. The formation of the serrated channels is attributed to the generation of oxygen gas bubbles and the resulted compressive stress on the oxide membrane. To reveal the inside channel structure, platinum is electrodeposited into the template. The as-synthesized serrated Pt nanowires demonstrate a superior electrocatalytic activity due to significantly enhanced electric field strength around serrated tips. Moreover, hierarchical serrated/straight hybrid structures are constructed using this simple and innovative self-assembly technique.