Odorous compounds in the influent of a reclaimed water treatment plant (RWTP),consisting of coagulation,sedimentation,continuous micro-filtration (CMF),and chlorination in succession,in a north China city,were identified by combining flavor profile analysis (FPA) with sensory gas chromatograph-mass spectrometry (GC-MS).The sewery/swampy/septic odor with an odor intensity of 6.4 was found to be the major odor group in the RWTP influent,and the existence of well-known odorant including dimethyl disulfide,dimethyl trisulfide,indole and skatole were confirmed using GC-MS.The result of a spiking test showed that the intensity (3.6) of the sewery/swampy/septic odor caused by these four chemicals contributed to over 50％ of the odor intensity of the influent.The FPA intensity for sewery/swampy/septic odor in the RWTP effluent was 3.8,showing that the treatment process was not efficient for the removal of odorants,particularly indole and skatole.