The field of small molecule electro-activated conversion is becoming a new star in modern catalytic research toward the carbon-neutral future. The advent of single-atom catalysts (SACs) is expected to greatly accelerate the kinetics of electrocatalytic reactions such as the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR), etc., owing to their maximum atomic efficiency, unique quantized energy level structure and strong interaction between well-defined active sites and supports. In this feature article, our group's proposed synthesis methodology applied in electrocatalysis is mainly summarized. Furthermore, we elaborate on how to achieve the stabilization of single metal atoms against migration and agglomeration during the preparation of SACs. Moreover, the electrochemical applications of SACs with a focus on the above heterogeneous reactions are presented. Finally, the prospects for the development and deficiencies of these SACs for electrocatalytic reactions are discussed.