Fujiang River is an important source of drinking water in Jiangyou city, once suffering pollution from upstream water, it is necessary to be replaced by water supply in the emergency water source in time. According to the characteristics of the watershed, Qinglian town is selected as the emergency water source of Jiangyou city. Through the investigation and study on the quantity of groundwater resources in Qinglian town, the groundwater recharge, storage and consumption in this area are comprehensively studied, and the water samples of the water source are collected and analyzed to obtain the hydrochemical characteristics of the water source. The results show that the groundwater quantity and quality of Qinglian town meet the requirements of emergency water source of Jiangyou city. Finally, the suitability of emergency water source in Jiangyou city is evaluated by means of AHP.