Developing effective non-precious metal catalysts for oxygen reduction reaction (ORR) is of great importance in a wide range of clean electrochemical energy conversion technologies. In this work, N-free heteroatoms (B, S) single- and dual-doped Co/C catalysts for ORR are synthesized, characterized and compared with respect to their ORR catalytic performances. Electrochemical results show that BS-Co/C has a high ORR catalytic performance with an ORR peak potential (865 mV) and a half-wave potential (850 mV), better than both B-Co/C (842 mV and 818 mV) and S-Co/C (859 mV and 842 mV). Moreover, BS-Co/C has a main 4-electron ORR pathway, a good stability and strong methanol-tolerance. Compared to B-Co/C and S-Co/C, a synergistic ORR catalysis of BS-Co/C is observed in this work. The results of several structural characterizations indicate that this BS-Co/C possesses a structure of B and S dual-doped carbon with amorphous Co to improve the ORR catalytic performance.