The development of high atomic economic efficiency catalysts for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) are important for the large-scale application of renewable energy technologies but still challenging. Herein, we reported a novel encapsulation-adsorption-pyrolysis strategy for the construction of atomically dispersed Co-Te diatomic sites (DASs) that are anchored in N-doped carbon (N-C) as efficient bifunctional catalyst for synergistic electrocatalytic HER and ORR. The as-constructed catalyst has stable and special CoN3C1-TeN1C3 coordination structures, Coδ+ has adsorption-activation function and the neighbouring Teδ+ acts as an electron donor adjusting the electronic structure of Coδ+, promoting the dissociation of H2O molecules and the adsorption of H and oxygen-containing intermediates in HER and ORR. This work provides numerous new opportunities to rational design and artificial synthesis of DASs catalysts for energy conversion.