Fires are one of the common challenges faced by smart cities. As the foundation of smart fire-fighting, urban fire risk assessment could help well understand the fire situation faced by a smart city, thus effective decision-making support for government and fire department could be provided. This work is aimed at further exploring the construction of urban fire risk assessment index system for smart cities. Urban fire history statistics analysis is performed. Besides, fire risk assessment indicators are discussed and selected based on theoretical analysis. Furthermore, urban fire risk assessment index system is built by the Analytic Hierarchy Process (AHP), which is of great significance to promote the application of smart fire-fighting in smart city construction.