© 2021The electrochemical conversion of carbon dioxide into low carbon fuels is a very convenient way of reducing the concentration of atmospheric CO2, which is the main cause of global warming. CO is known to be the most common and profitable product of CO2 reduction due to its low energy requirement and reaction simplicity. However, the viability of the process still depends on affordable and efficient catalysts. In this review, an overview is provided on recent advances in developing highly efficient heterogeneous catalysts for the selective electroreduction of CO2 to CO, particularly considering the results of mechanistic investigations and the fulfillment of the basic catalytic requirements. Recent progress in the heterogeneous electrocatalysts is reviewed in a concise manner as much as possible by examining what is achieved from the different combinations of transition metals with a considerable variety of supporting materials such as metal-organic-frameworks, graphene-like carbonaceous materials, nitrogen-doped carbons, and other new-generation supports. The review also includes the comparison of the electrocatalysts used for the selective reduction of CO2 to CO in terms of catalytic efficiency and addresses the current challenges which need to be considered in designing future research works in the field.