This research is carried out to investigate the odor emission characteristics in a sewage treatment plant. The plant was divided into four areas (boundary areas, sewage treatment processes, sludge treatment processes and odor treatment plants), and measured around 27 sampling points. Odor characteristics from each areas were evaluated by air dilution olfactory method and NH3/SO2/VOCs passive sampler, mainly in terms of spatial distribution. The main odor emission sources were found out to be dewatering plant (S-4) of sludge, sludge transshipment place(S-5), and the outlet of odor treatment plant (B-2, B-3). The correlation between dilution number (OU) and ammonia concentration of passive sampler appeared to be low; correlation coefficient 0.49, but correlation coefficient for the results of sulfur dioxide and toluene were very high, 0.95 and 0.93, respectively. These results indicate that odor compounds form sewage treatment facility are mainly due to sulfur compounds and volatile organic compounds. Keywords : Odor, Sewage treatment facility, Passive sampler, Air dilution olfactory method