This study analyses the affectivity of social disgust behind the oppressive exclusion of social minorities, such as the forced institutionalisation of vagrants in modern Korean society. This social exclusion of vagrants is divided into two forms: the forced institutionalisation of ‘infected vagrants’ during the Japanese occupation and the forced institutionalisation of ‘vagrants themselves’ during the developmental state. In both cases, the visible power apparatus of exclusion of minorities was socially legitimised by the effective use of disgust politics of purification and isolation. Through this analysis, this study joins the discourse on affective communities as a critical alternative to deinstitutionalisation by revealing the dynamics of the social disgust that threatens the community’s existence.