Tobacco-free policies on college campuses are spreading in Korea. However, the impact of the smoking ban legislation at venues on the boundary of a college campus is still limited. This study aimed to assess short-term changes in PM2.5 concentrations before and after the enactment of the smoking ban legislation to evaluate the impact. In this cross-sectional study, PM2.5 measurements (pre-ban: n = 99, post-ban: n = 64) were conducted in randomly selected billiards, pubs, and computer game rooms on the peripheries of college campuses in October 2013, prior to implementation of the smoking ban, and in May 2014, after the ban. The median (interquartile range, IQR) of the PM2.5 concentration for all venues was 31 μg/m³ (0-80 μg/m³) in the pre-ban period and 11 μg/m³ (0-36 μg/m³) in the post-ban period implying indoor PM2.5 concentration levels of the peripheries of college campuses likely decreased one year after implementation of the ban. However, the differences were not significant yet. The results support the introduction of more rigorous monitoring of SHS exposure levels toward the ultimate goal of encouraging a complete smoking ban in hospitality venues, including billiards, pubs, and computer game rooms located on the peripheries of college campuses.