In order to solve technical problems of drought analysis and drought-resistance decision making in cities, a new idea of urban drought risk control was put forward, and a system dynamics model of urban water supply network was constructed based on analysis of socio-economic drought characteristics. Taking the water supply region of Gongping Reservoir in Shanwei City of Guangdong Province as an example, the development trend of drought was deduced with hydrological drought as the input condition, and the effect of drought-resistance measures in drought risk control was evaluated quantitatively. The results show that under the extreme drought scenario, the basic water demand of the water supply region of Gongping Reservoir can be guaranteed during the operation period by adopting comprehensive measures, including reducing domestic water consumption, restricting water use in agriculture, industry, and ecology, replenishing reservoir water, implementing the Huangjiang River emergency project of water supply, and using the dead storage capacity of the reservoir for water supply. The established urban water supply network system dynamics model reveals the chain transmission mechanism of hydrological drought to socio-economic drought, and realizes the accurate simulation of socio-economic drought and the feedback and inference of drought-resistance measures.