According to the development of GC equipment, it has been possible to analyze the low level of ambient VOCs concentration. In this study, the limit of detection and the limit of quantitation were estimated for two GC equipments of the VOCs analysis, which would contribute to improve the quality of VOCs analysis results. The results of %RSD for ten standard solutes showed a great reproducibility in terms of detection time and detection area. The limit of detection and the limit of quantitation in SRI GC appeared to be 0.175 ppb and 0.583 ppb for benzene, and 0.223 ppb and 0.743 ppb for toluene, respectively. On the other hand, The limit of detection and the limit of quantitation in FISON GC appeared to be 0.149 ppb and 0.496 ppb for benzene, and 0.094 ppb and 0.313 ppb for toluene, respectively.