The spectral characteristics of different kinds of oil, either from plant seeds or animal fat, were studied with Raman spectroscopy. The experimental data were processed with the adaptive iteratively reweighted penalized least squares method to realize baseline correction, and provide evident information about their microscopic world. The spectra were analyzed and compared with each other in three parts: the Raman spectra comparison among different samples of plant oils, the analysis of the animal fat and the comparison between plant oils and the animal fat. The differences among the oils were observed in the analysis, including Raman shift and Raman intensity differences. This study not only yields the spectral basis for distinguishing or recognizing the different edible oils, but also confirms that Raman spectroscopy is an effective tool for identifying different oils.