Understanding CO2 reduction reaction (CO2RR) and developing robust catalysts for selective CO2RR is key to closing carbon cycle and to achieving energy sustainability with desired environmental remediation. Electrochemical CO2RR on a catalyst surface is an attractive method to realize high reaction activity and selectivity under mild reaction conditions. Among various catalysts studied thus far, metallic Cu-based nanocatalysts have demonstrated to be promising for selective CO2RR to HCOOH, CO or, more importantly, to CH4, C2H4 and C2H6 with relatively high efficiency. This review summarizes recent progresses made on these Cu-based nanocatalysts for CO2RR, including fundamental of electrochemical CO2RR, representative approaches to Cu-based nanocatalysts via nanoporous structure, nanoparticle size, composition, surface, support and morphology controls. The review should offer readers some important insights on Cu-catalyzed CO2RR, and will further help readers in their efforts to design and develop robust catalysts for active and selective CO2RR. (C) 2018 Elsevier Ltd. All rights reserved.