Recently, the number of accidents reported involving foreign laborers has risen, and the need to prevent accidents at construction sites has become more urgent. It has been found that 90 percent of construction accidents are caused by unsafe work practices, and various studies have been conducted on these practices with the aim of preventing accidents at construction sites. However, the tendency with previous studies was to average the results of survey responses, and as a result it is impossible to consider the potential risk of how many foreign laborers feel unsafe in relation with the unsafe practices. Therefore, in this study, importance-performance analysis (IPA) was improved in order to assess the potential risk of the unsafe practices of foreign laborers at construction sites in Korea. To verify the applicability of the improved IPA, a survey was carried out, and then the results were compared with those of the IPA. Through the use of the improved IPA, unsafe practices that were not found in the previous IPA but have potential risk were identified. The method proposed in this study is expected to contribute to the prevention of construction accidents of foreign workers by enabling a more efficient management.