The purpose of this study is to develop a vulnerability assessment model of explosive terrorism in multi-use buildings focusing mainly on architectural design elements. First, in order to extract the weights of each assessment element, expert surveys with four anti-terrorism specialists were conducted twice. The results imply that the risk of bomb attack in buildings is influenced more by the vulnerability of the layers of defense, the supplementary groups, and the scenarios of explosion than by the vulnerability of assessment elements. Second, the vulnerability assessment model was developed to calculate the vulnerability level of each layer of defense and scenario of explosive terrorism individually as well as the overall vulnerability level of a building. This model reflects the relative importance and supplementary effects of elements. Third, two multi-use buildings were assessed using the developed model to analyze the vulnerability level of each layer of defense, supplementary group, and the entire building. Based on the results of the case study, cost-efficient design alternatives to reduce the vulnerability of a building were presented.@en