Smart city has the function of improving enterprise innovation. Based on multi-point DID, the paper examines the impact of macro-mechanism such as labor agglomeration, capital intensity, infrastructure upgrading, industrial transformation on the relationship between Smart City and Enterprise Innovation.This article finds that smart city pilot can significantly affect enterprise innovation. The reason for this is that smart city has the "siphon effect", which can bring in talents, increase investment, innovate technology, and upgrade industry, thus producing knowledge spillover and technology spillover, which can help improve enterprise innovation investment.