Dismantling administrative monopoly is an inherent requirement for building a unified national market and serves as a foundational support for establishing a new development paradigm. From a legal perspective, this paper examines the intrinsic logic linking administrative monopoly regulation, unified national market construction, and corporate innovation through an analysis of relevant enforcement cases and Chinese tax survey data spanning 2007 to 2016. The study finds that the administrative monopoly regulation through enforcement practices significantly promotes corporate innovation. Mechanism analysis indicates that administrative monopoly regulation primarily facilitates the unified national market construction by strengthening market competition and optimizing the efficiency of innovation resource allocation, thereby advancing corporate innovation. Heterogeneity analysis reveals that the promoting effect of administrative monopoly regulation on corporate innovation is more pronounced for samples comprising industry leaders, non-state-owned corporations, and corporations in regions with higher judicial transparency and greater initial market segmentation. Furthermore, this study demonstrates that administrative monopoly regulation aids in clearing out zombie corporates and stimulating regional entrepreneurial vitality. This research holds significant policy implications for promoting the establishment of a high-standard market system and constructing a new development paradigm.