The real estate industry is an important indicator of national economic growth and development, which is influenced by the environment in which it operates. Various countries have been seriously affected by the most recent international financial crisis. Nevertheless, regardless of the challenges some cities currently face and the impacts on their sustainable livability, urban real estate is still of interest to investors. Given this context, researchers have sought to develop and apply methods of evaluating sustainable livability in cities. However, most practical applications have been hampered by methodological limitations (e.g., how to select and weight criteria in evaluations), which has hampered progress in this area. The present study thus aimed to develop a knowledge-based decision support system to evaluate city sustainability and livability in a transparent and informed way. To achieve its goal, this research combined cognitive mapping techniques and the analytic hierarchy process (AHP). Based on real-world data, the advantages and limitations of this integrative evaluation system are discussed.