The electroreduction of carbon dioxide (CO 2 ) to hydrocarbons has been proposed as a promising way to utilize CO 2 and maintain the ecosystem carbon balance. However, the selective reduction of CO 2 to hydrocarbons (such as methane and ethylene) is still a challenge. Herein, we developed a highly efficient heterostructured catalyst that contains carbon nitride-encapsulated copper oxide hybrid (Cu x O/CN). The interaction between the metal and carbon nitride in the heterostructured catalysts improves the intrinsic electrical conductivity and the charge transfer processes via the catalyst-support interfaces. A remarkable enhancement in the selectivity of hydrocarbons is achieved with these modified Cu-based electrocatalysts, with an onset potential of -0.4 V and high C 2 H 4 Faradaic efficiency of 42.2%, and these catalysts can effectively suppress H 2 evolution during the CO 2 reduction reaction. This work provides a simple and cost-effective method for synthesizing CN co-encapsulated catalysts that provides the possibility of efficiently converting CO 2 into C 2 hydrocarbons.