This paper looks to the rearticulations that are currently underway in the Chinese territories that are identifiable as “mid-small cities”, summarizing the characteristics of the HSR construction in the pioneer countries (Japan, France, Germany…) and the benefits the HSR brings, then showing the development process of China’s HSR construction, the significance of China’s HSR construction to its domestic urbanization, the regional development of coastal and interior areas and the development of trade ties with neighboring countries. At the same time, based on the panel data of Shanghai–Wuhan–Chengdu passenger railway during the period of 2009-2019, this essay evaluates the influence of HSR construction on non-first-tier cities’ urban population scale and urbanization level with the spatial panel analysis.