Although urban big data holds significant potential for transforming the way cities are managed, harnessing this potential requires overcoming major challenges, particularly in developing countries like Iran. Obstacles like policy gaps, legal barriers, limited resources for data management and infrastructure or even the low level of community engagement and the lack of technological capabilities could backward the development of becoming a real data-driven smart city. This study aims to address the understanding of this issue, by identifying and evaluating urban big data challenges critically, and to formulate policy-related support for governmental bodies in a country considered to be a developing information society. After thorough analysis of academic publications we identified 32 urban big data challenges in Iran, which then were systematically evaluated and ranked by Analytic Hierarchy Process (AHP) methodology based on expert surveys. Outcomes confirmed that although social, educational and financial challenges have been perceived, the most important ones are of political and governmental origin.