Sustainable development of cities is a concept that strives to create a harmonious environment for life, ensuring economic progress and social justice. The purpose of the research was to analyze the level of sustainable development of cities of republican importance — Almaty, Astana and Shymkent — using Shannon's entropy approach. Research methodology included the process of normalization of data on economic, industrial, labor and social indicators for the three cities. Data normalization was performed by standardizing measurements to ensure comparability, considering both positive and negative values of indicators. The urbanization index for each city was derived by aggregating the normalized values of indicators, which allowed to obtain a comprehensive assessment of the level of urban development. This ensured the formation of a ranked picture of urbanization, in which each city is represented on a relative scale of urbanization from the lowest to the highest level. The findings of the study allowed highlighting key aspects that require attention to improve the sustainable development of cities. The main results of the study revealed differences in the level of sustainable development between Almaty, Astana and Shymkent cities. Almaty and Astana showed higher values of entropy, which reflects a more complex and diversified economic and social structure. Shymkent, despite its strategic position and role in the regional economy, demonstrates a lower level of urbanization, which may reflect both the presence of certain obstacles to development and the potential for further economic growth and urbanization.