Objectives: We measured the concentrations of culturable airborne fungi (CAF) in enclosed environments at 16 underground subway stations of the Seoul Metro in 2013, and investigated the effect of environmental factors, including temperature, relative humidity, the number of passengers, and distance from the platform. Methods: The cultured fungi were identified by the lactophenol cotton blue (LPCB) staining method and were classified by observing the form, shape, and color of colony. A nonparametric analysis was used to determine if the differences in the concentrations of CAF were statistically significant. Results: The concentrations of CAF at the stations were the highest in station p ($367CFU/m^3$) with arange between 3 and $437CFU/m^3$. There was a significant correlation between CAF concentration and the distance from platform (r = 0.544, p < 0.01). Geotrichum spp. and Penicillium spp. were the predominant species. Conclusion: It is recommended that special attention be given during rush hour, which is in the morning (08:00-10:00) and in the early evening (18:00-19:00) to improve the indoor air quality of the subway stations.