Smart cities, as a product of the deep integration of digital technology and urban development, are not only a vital part of achieving the vision of a strong network nation and digital China but also a key practical approach to driving the intelligent transformation of cities and empowering them with digital technology. This paper, based on panel data from 207 Chinese cities from 2008 to 2019, employs the difference-in-differences method to explore the impact of smart city construction on the level of industrial intelligence in cities. It further analyzes the heterogeneity and mechanisms of this impact. The main conclusions drawn from the study are as follows: First, compared to non-pilot cities, the construction of smart cities significantly enhances the level of industrial intelligence in pilot cities. This conclusion holds true even after a series of robustness tests. Second, the positive impact of smart city construction on the level of industrial intelligence is primarily concentrated in eastern cities, cities with a high level of digital economy development, and cities with strong innovation capabilities. The impact is less significant or negligible in central and western cities, cities with a lower level of digital economy development, and cities with weaker innovation capabilities. Third, the construction of smart cities promotes the development of industrial intelligence in cities by enhancing urban innovation capabilities and improving the development level of new infrastructure.