Abstract: In order to meet the monitoring requirements for drinking water sources, purge-and-trap gas chromatographymass spectrometry (P&TGC-MS) was used to simultaneously determine 27 kinds of volatile organic compounds (VOCs), such as acetaldehyde, epichlorohydrin, acrolein, benzene series etc. The programmed temperature was used to shorten the running time to 26 minutes for one measurement. Fullscan mode was used to increase the ability for qualitative analysis of VOCs. The detection limits was less than the standard limits for drinking water sources in China and the recovery was 75.6%～111.0%.