In response to the urgent global need for sustainable urban development, this thesis explores the application of urban metabolism as a framework to transform Tabriz, a major Iranian city, into a more resource-efficient and ecologically balanced urban system. Urban metabolism interprets the city as a living organism that consumes, transforms, and expels resources. By analyzing the city through this lens, the research identifies key material and energy flows - water, energy, waste, and food - that can be optimized to reduce environmental impact and enhance urban resilience. After a review of existing literature on urban metabolism and international case studies, the thesis focuses on the case of Tabriz.