In order to provide a better service of water pollution emergency monitoring,the paper described the adoption case of Fourier transform infrared multi-component gas analyzer with headspace theory.The process included identifying the gas-phase pollutants from the water samples,screening the main pollutants quickly and qualitatively,and then choosing the standard method to quantify the concentrations of corresponding targets.Thus the research provided an efficient method for emergency monitoring which showed the advantages of wide determination range,fast qualitatively screening and instruments easy to carry.