<p>The performance of China's rapid urbanization is critical for the successful implementation of the 2030 Agenda for Sustainable Development. In response to challenges such as environmental pollution, social inequality, and resource scarcity, China has proposed and enacted a new urbanization strategy. However, it remains to be evaluated whether this new approach to urbanization aligns with the principles of sustainable development and whether it is genuinely sustainable. This study constructs an indicator system tailored to measure the sustainability of urbanization at both the national and provincial levels in China. It then uses the United Nations Sustainable Development Goals index calculation method to assess urbanization sustainability separately at these two levels. The findings regarding urbanization sustainability are then integrated with the urbanization rate, and the elasticity coefficient method is employed to evaluate the status of sustainable urbanization in China from 2010 to 2021. The results show a steady improvement in the sustainability of urbanization in China from 2010 to 2021, with environmental performance surpassing social and economic dimensions. Although eastern provinces consistently outperformed their central and western counterparts, regional disparities have gradually narrowed over time. Most provinces experienced notable progress in multiple dimensions, while a few, including Shaanxi, Chongqing, Guizhou, and Hainan, showed signs of regression. Among the 17 goals, SDG 16 was the only one to exhibit a negative trend, primarily due to the insufficient number of legal professionals relative to population growth. This study provides references and recommendations for the future promotion of sustainable urbanization in China, as well as insights for the practice and research of sustainable urbanization in other countries.</p>