Abstract: Using TM image and statistical yearbook data of the Yellow River source in Gannan area, Gansu Province, along with vegetation coverage, water conservation, land use pattern, population density and agricultural and animal products as ecological factors, the eco-economic functional regionalization of important water supply region of the Yellow River in Gannan was conducted. An analytical hierarchy process was developed to weigh ecological factors in study area. Based on the weights of the ecological factors, the Yellow River source region in Gannan was classified into town construction and eco-agricultural economy zone, hydro-ecological recharge zone of the Yellow River, eco-agricultural economy zone of the Tao River, livestock product supply and ecological tourism zone, and livestock product supply zone of Maqu. The ecological characteristics and problems in eco-economic development of different zones were discussed through analysis on the internal connection among different zones. The developmental directions, ways and countermeasures were also advanced. The findings of the research could provide guidelines for protecting, constructing and developing the study area.