The structure- and composition-controlled synthesis of Pt-based nanocatalysts is highly important for improving their catalytic performance while reducing the overall use of precious Pt. Here, an effective strategy is developed to combine surface porosity, hollow cavities and metal–nonmetal incorporation engineering on Pt, resulting in ternary Pt–Ni–P mesoporous nanocages (Pt–Ni–P MNCs). Owing to the mesoporous surface, hollow structure and synergistic electronic effects derived from Pt, Ni, and P elements, the as-prepared Pt–Ni–P MNCs exhibit excellent electrocatalytic activity and long-term stability for both the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR), enabling them to be promising ORR–MOR bifunctional electrocatalysts for direct methanol fuel cells.