Porous ternary PtRuCo catalyst supported on a glassy carbon substrate was prepared by one-step electrochemical codeposition using an adsorbed hydrogen gas bubble as a dynamic template. The as-prepared catalyst was characterized by scanning electron microscopy and transmission electron microscopy. Methanol electro-oxidation on the as-prepared catalyst was investigated by cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy, and the results show that porous ternary PtRuCo catalyst has excellent electrocatalytic performance.