Abstract: After methylation of rapeseed oil,soya bean oil and jatrophaoil,the similarities and differences of the characteristic peak of raw oil and methylated biodiesel samples were analyzed by FTIR.The major compositions of the biodiesel samples were analyzed by gas chromatography - mass spectrometry (GC-MS).Different ratios of methyl oleate and methyl stearate were added into biodiesel samples respectively,then the effects of fatty acid methyl esters on the oxidative induction period and heat value were investigated.Theoretical parameter of C-H bond dissociation energies (BDEs) of methyl oleate and methyl stearate were calculated by using Gaussian09.The results show that the effect of methyl stearate on the oxidation induction period of biodiesel samples was more obvious than that of methyl stearate,and simulation results were consistent with experimental results.After adding fatty acid methyl ester in biodiesel,the heat value increased with the increase of the adding amount of single fatty acid methyl ester,which was close to the heat value of single fatty acid methyl ester.