Abstract: In the context of innovation-driven development, improving carbon emission efficiency is a key link to achieve green and low-carbon development. Based on the quasi-natural experiment of pilot construction of innovation-oriented cities, an analysis framework of enterprise heterogeneity was constructed to analyze the impact of pilot policies on urban carbon emission efficiency, transmission mechanism and spatial-temporal heterogeneity from theoretical and empirical perspectives. Panel data of 282 prefecture-level cities from 2006 to 2020 were used for verification. The results show that:Pilot policies of innovation-oriented cities can significantly promote the improvement of urban carbon emission efficiency; In terms of influencing mechanism, pilot policies of innovation-oriented cities will improve urban carbon emission efficiency through green technology innovation and industrial structure optimization; The effect of innovation pilot policies on the improvement of carbon emission efficiency is differentiated in different regions, different industrial bases and cities of different sizes; From the spatial perspective, the promotion effect of innovation pilot policies on carbon emission efficiency has a spatial spillover effect, which will significantly drive the improvement of carbon emission efficiency of cities within 150 km to 250 km.

Key words: innovative city pilot, carbon emission efficiency, multiphase differential model, space decay law