Anthropogenic accumulation of atmospheric carbon dioxide (CO2) rises many environmental issues, including global warming, ocean acidification, and glacial ablation. Electrocatalytic carbon dioxide reduction reaction (CO2RR) is an efficient approach to reducing atmospheric CO2 concentration as well as producing value-added chemicals. Single-atom electrocatalysts (SAECs) have attracted much attention due to their remarkable electrocatalytic performance. The synthetic methods of SAECs can significantly affect the structure and, thus the catalytic performance of energy conversion reactions like CO2RR. However, the underlying mechanism of the impacts has been largely overlooked. The focus of this short review is to reveal the correlation of synthetic methods with the catalytic performance of SAECs for CO2RR and provide insights for future research in this field.