In this paper, for the first time, a rationally designed strategy for synthesis of Co nanoparticles encapsulated by boron and nitrogen co-doped carbon nanosheets, namely B, N-Co/CNs, as highly efficient electrocatalyst for oxygen reduction reaction was demonstrated. The generated Co nanoparticles not only create well-defined heterointerfaces with high conductivity to overcome the poor oxygen reduction reaction (ORR) activity but also promote the formation of robust graphitic carbon. The co-existence of boron and nitrogen atoms can increase the highest occupied molecular orbital energy of sp2 hybridization, activating π electrons in graphitic carbon nanosheets, thereby enhancing the activity of the catalyst. The B, N-Co/CNs exhibit a comparable half-wave potential (E_1/2 = 0.83 V) to that of commercial Pt/C catalyst (E_1/2 = 0.85 V) with a larger current density for ORR. Importantly, the homemade disposable Zn-air battery (ZAB) is able to deliver excellent performance, including a peak power density of 93.93 mW cm^?2 and a specific capacity of 727.5 mAh g^?1, outperforming the Pt/C catalyst. The findings highlight a new guideline for constructing B, N-Co/CNs catalyst with a rationally designed structure toward superior property for advanced metal-air cathode materials.