Abstract: Under the context of China’s new development paradigm, the construction of a unified national market provides substantial institutional guarantees for dismantling market access barriers and fostering a fair business environment. Evaluating its impact on the high-quality development of private enterprises is of significant practical relevance. Using panel data from Chinese privately listed firms and prefecture-level cities from 2005 to 2022, this paper empirically examines the influence of unified national market building on the total factor productivity (TFP) of private enterprises. The findings indicate that the development of a unified national market significantly enhances the TFP of private firms. Specifically, the removal of local protectionism, the innovation effect, and the regional coordination effect serve as the primary channels through which the unified national market boosts private firms’ TFP. The effect is more pronounced among non-exporting firms, enterprises lagging in digital transformation, labor-intensive industries, as well as in cities outside major urban clusters, with lower population density, and less healthy government-business relations. Further analysis reveals that urban spatial connectivity leads to positive spillover effects, whereby the advancement of the unified national market in neighboring regions also improves local private firms’ TFP. This study provides empirical evidence and practical insights for promoting the growth and strengthening of the private economy.

Key words: national unified market, private economy, high-quality development, total factor productivity