Odor emission characteristics of unit processes in 10 livestock farms and 3 manure treatment facilities in Kyonggi province were examined in terms of odorous compound concentration and dilution ratio values of the threshold limit measured by instrumental analysis and air dilution sensory test, respectively. The highest odor concentration was detected at the compositing process unit of each facility and the dilution ratio showed high correlation with the treatment capacity as well as hygiene of the facility. Odor intensities in some facilities showed severe fluctuations (10 to 27 times difference) in response to the wind speed and direction as well as other weather conditions. According to the instrumental analysis, the major odorous compounds in the research area appeared to be ammonia, hydrogen sulfide, trimethyl amine, acetaldehyde and carbonyl compounds. Although some facilities breed same livestock, the types of odorous compounds as well as their concentration profiles were dependent on the type of composting process and management skill. In addition, dilution ratio of the threshold limit did not always show positive correlation with the odorous compound concentrations, which indicates the necessity of applying both methodologies, sensory test, and instrumental analysis.