The Third Plenary Session of the 20th CPC Central Committee emphasized that it is necessary to accelerate the development of new quality productivity, promote the deep integration of green and lowcarbon transformation and the construction of digital China, and enhance the city’s innovationdriven development capability In this paper, the superposition effect and mechanism of innovative city, smart city and broadband China on urban green innovation are systematically investigated based on quasinatural experiments The research findings are as follows: (1) The “three pilot” policy has significantly improved the level of urban green innovation Further structural decomposition analysis shows that the policy combination still plays a significant role in promoting substantive green innovation and strategic green innovation, and the conclusion is still stable after excluding the preeffect (2) The mechanism test shows that the embeddedness of knowledge network and the intensity of environmental regulation are two effective paths (3) The expansibility analysis shows that the “three pilot projects” have more prominent advantages in collaborative governance, and the pilot order will affect the governance effect (4) The pilot cities have significant spatial spillover effects on neighboring nonpilot cities To sum up, in the future, we should further optimize the collaborative promotion path of innovation ecology, smart governance and digital infrastructure in order to provide institutional guarantee for green and lowcarbon transformation and the cultivation of new quality productivity