In the case of major public emergencies, the ability of cities to resist shocks becomes very important and reflects urban resilience. This paper selects the supply guarantee facilities during the city-wide lockdown of Shanghai during March-May 2022 due to COVID-19 pandemic as the research object. In this research, the thermodynamic diagram map generated based on cell phone visits reflects the actual distribution of population, and the per capita supply guarantee capacity and supply guarantee overlay intensity are analyzed based on official list of facilities, and the actual role of the supply guarantee facilities are investigated through a public research questionnaire. Based on these analyses, the level of “supply guarantee resilience” was evaluated and graded for each district of Shanghai. It was concluded that the overall level of supply guarantee resilience was high in the central city, divergence in the near suburban districts, and generally low in the remote suburban districts. Based on this, the paper summarize the problems of supply guarantee revealed in Shanghai during the epidemic lockdown and propose strategies to improve the resilience of similar scenarios in the future. With the help of big data and public research tools, this paper aims to provide ways and methods to evaluate the resilience of cities under major public emergencies.