This study aims to understand the correlation between odor intensity and dilution factor using the Air Dilution Olfactory Method, which is suggested in the Standard Method of Odor Compounds, by measuring odor intensity and dilution factor for fatty acids and i-butyl alcohol. For the measurement, 18 panel members were selected through a panel test, and odor intensity and dilution factor by substance produced from the selected panel were estimated. The estimation showed that the correlation of odor intensity with dilution factor for a fatty acids and i-butyl alcohol can be reasonably expressed by the equation I = A·log D + 0.5 (I : odor Intensity, D : dilution factor, A : material constant). The material constant was in order of propionic acid 2.0709, n-butyric acid 1.6006, n-valeric acid 1.3369, i-valeric acid 1.182, i-butyl alcohol 1.4326. The geometric average of increased dilution factor for the 5 compounds is about 4.8 time, 3.0 time for propionic acid and 7.0 tme for i-valeric acid due to odor intensity 1 increasing. It is suggested that the result of this study could be used as a base data for research on measures to improve the regulation standards for complex odor concentrations at a boundary sites in operation. Keywords : Correlation equation, Dilution factor, Fatty acids, i-Butyl alcohol, Odor intensity