The inherent characteristics of energy resources in China determine that the fundamental status of coal as the primary energy source is unlikely to change in the short term, and coal remains the cornerstone of China's energy security. Currently, Shanxi, Shaanxi, and Inner Mongolia are the main coal production bases in China, with coal production accounting for over 80% of the national total, providing reliable energy security for the high-quality development of the national economy. The coal industry is the pillar industry of Shanxi, Shaanxi, and Inner Mongolia, with over 80% of the municipalities being coal resource-based cities, whose local economies prosper and are also constrained by coal. The typical cyclical development of the coal industry has brought about serious environmental pollution problems to coal resource-based cities, to some extent restricting the sustainable development of cities. Therefore, based on the characteristics of coal resource-based cities and guided by the goal of high-quality development, this study constructs a comprehensive evaluation index system for green development and utilizes the entropy method to explore the key factors influencing the green development of coal resource-based cities. Moreover, it proposes strategies for the green transformation of coal resource-based cities to overcome these challenges, providing a basis and reference for the sustainable development of coal resource-based cities.