With the global economic landscape shifts and the growing demand for domestic high-quality economic development, the unified national market has emerged as a key strategic initiative to promote domestic and international dual circulation. Its core objective is to eliminate market barriers, optimize resource allocation, and enhance market efficiency, creating a high-performing, equitable, and transparent market system. The framework has significant implications for integrating Chinese enterprises into domestic supply chain and international value chain.

This paper, set against China’s transition to a distinctive market economy, develops a theoretical model to analyze how the unified national market affects the positions of Chinese enterprises in domestic supply chain and international value chain. The study focuses on three key mechanisms: cost reduction, innovation enhancement, and environmental optimization. This paper uses data from China’s A-share listed companies from 2009 to 2015 and quantitatively evaluates the internal effect of building a unified national market on improving the positions. Additionally, it examines the heterogeneous effect of market integration across various dimensions, and investigates the role of the enhanced position in domestic supply chain in mediating the relationship between the construction of a unified national market and international value chain.

The findings reveal that the construction of a unified national market significantly enhances the positions of Chinese enterprises in domestic supply chain and international value chain. The policy effect varies considerably across enterprises based on ownership structure, trade type, geographic location, regional logistics competitiveness, and industry characteristics. Moreover, domestic supply chain is critical in positively moderating the relationship between the construction of a unified national market and international value chain. The results underscore the importance of optimizing the domestic market for enhancing international competitiveness. This paper contributes theoretical insights and policy recommendations to support enterprise competitiveness, strengthen domestic and international dual circulation, and advance high-quality market system construction.