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Thermogravimetry (TG) and derivative thermogravimetry (DTG) were used to investigate the thermal oxidative properties of six normal vegetable oils. The influence of different heating programs on the weight changing curves was studied and the onset oxidation temperature (Ton) and peak oxidation temperature (Tp) were located from the DTG curves. Through the application of Ozawa-Flynn-Wall iso-conventional method, the oxidation kinetic properties of oils were deduced and the correlation between thermal behaviors and triacylglycerol composition was analyzed. The results showed that both Ton and Tp were increased with the raise of heating rate and Tp was varied more sensitively, which indicated that the reactions occurred around Tp could be more acuminous to the change in surroundings. Varying degrees of correlation were found between thermal behaviors and triacylglycerol distribution: Ton and Ea(Ton) were found to be positively correlated with high saturated triacylglycerols but negatively correlated with high unsaturated ones. Similar results were found between Tp, Ea(Tp) and various components but with weaker correlations. Specific correlation was depended on the type of fatty acid chains on glycerol skeletons. Thus, predictions of oil thermal stability could be done according to thetriacylglycerol profiles. Thermogravimetry analysis was praised for trace sample size, fast operation and high sensitivity, which would show promising prospect in oil processing and quality control.