Oil adhered to beer container often becomes complaint of consumer. Since consumer's concern about food safety recently increase greatly, it is necessary to respond quickly to the complaints like that. For this reason, identification methods of oils were investigated and established. Vegetable oils and fourteen commercial machine oils were collected and investigated. At first infrared spectra were taken with FT-IR spectrometer. A silicon-oil, nine of thirteen hydrocarbon oils, and vegetable oils were differentiated by infrared spectra. The spectra of vegetable oils are characterized by absorption of stretch vibration of CO double bond at 1740 cm(^-1) and similarity to the spectra pattern. Then additives in oils were analyzed by heat desorption -GC/MS and chromatographic patterns of pyrolysates of oils were examined with pyrolysis -GC/MS. The results showed that nine of fourteen oils contained different additives and were distinguished each other. The remained five oils contained BHT as additive and have the same pattern of pyrograms. However, the remained undistinguished oils were discriminated each other with chart patterns of evolved gas -direct FID analysis (EGA). Thus, all oils were identified using these three analytical methods. It was found that the combination of FT-IR, heat desorption & pyrolysis -GC/MS, EGA is a useful method for identification of oils found on beer containers.