This study systematically investigates the impact of ecological civilization demonstration areas on eco-efficiency, utilizing the difference-in-differences method based on a dataset comprising 114 resource-based cities in China spanning the years 2006 to 2020. The results uncover a pattern where eco-efficiency is observed to be higher in eastern China and lower in western China, with an overall trend exhibiting fluctuating upward movement. Furthermore, the establishment of ecological civilization demonstration areas is found to exert a positive influence on enhancing eco-efficiency, notably via the channel of technological innovation. Additionally, the effects of ecological civilization demonstration areas on eco-efficiency exhibit significant variation across different zones and city characteristics, indicating the presence of divergent features.