To accelerate the building of a country with strong transportation network and a new energy system， and to promote the integrated development of the transportation infrastructure network and the energy network， the application of clean energy in China’s transportation sector is shifting from point‑scale demonstration to full‑domain integration. Driven by policies and technological innovation， expressways are emerging as new energy hubs that integrate photovoltaic power generation， energy storage and peak regulation， and green charging and battery swapping. This article， by systematically reviewing current research on the integrated development of transportation and energy， establishes a theoretical framework for transport-energy integration， and explores optimized paths for the multi-dimensional integrated development of transportation and energy in expressway systems. Research shows that promoting the integrated development of transportation and energy has shifted from single-point technological breakthroughs to the systematic restructuring of “policy–technology–mechanism”. At the policy level， it is necessary to strengthen coordination between national goals and local innovation， and break through constraints on land use and approval. At the technology level， efforts should be made to deepen the dynamic matching of source–grid–load–storage and multi-scenario adaptability， and improve system efficiency through AI prediction. At the mechanism level， it is imperative to accelerate the development of the green electricity trading market and business model innovation. To support the large-scale application of transport-energy integration， a three-dimensional policy framework covering the transportation sector， power sector， and commercial development models should be established： To be specific， a five-in-one policy framework of “planning coordination， approval optimization， standard guidance， land use innovation， and supervision strengthening” should be built at transportation sector to accelerate the deep integration of transportation networks and energy networks； an efficient and secure renewable electricity application system should be established to improve system operation reliability and cross-regional green electricity allocation capacity； an integrated “PV–storage–charging” business model for expressways should be developed to drive the transformation of transport–energy integration from demonstration applications to large-scale and industrialized development.