Public health emergencies，represented by large-scale infectious diseases，are modern risks that pose life-threatening crises for human beings and bring social and cultural changes. Quarantine and isolation are crucial measures in epidemic prevention considered as a modern risk. Due to the regional lockdown，atomized modern individuals in urban areas are confined to the same community space and have developed spiritual connections and group identities，thus forming a risk community due to the common risks they face. Within the risk community，interpersonal solidarity and conflicts coexist，creating tensions caused by risk awareness. Externally，the risk community has clear boundaries but is also exclusive. In the Chinese context of risk response，the tension between the prudent expansion of the logic of state control and the narrowing of individual logic of defense at the boundary shapes the characteristics of this new form of interpersonal relationship，the risk community.