As an important indicator of sustainability, eco-efficiency quantitatively describes the level of coordination between the social economy and ecological environment in regional development and therefore, it can be used as a basis for the construction of ecological civilization. Following a systematic review of the definition and connotation of eco-efficiency, this study summarizes the recent progress in regional eco-efficiency research:in terms of research methodology, model simulations are replacing single ratios; in terms of research objective, spatio-temporal dynamics are replacing static assessment; and in terms of research content, mechanism identification is replacing efficiency measurement. Subsequently, future directions for regional eco-efficiency research are outlined, that is, spatio-temporal analysis with geographical big data, model development with multi-factor integration, a special focus on regional urbanization, and sustainable governance of regional development.