Triacylglycerols (TAGs) and free fatty acids compositions of broccoli seed oil were analyzed using ultra-performance convergence chromatography (UPC2) combined with quadrupole time-of-flight mass spectrometry(Q-TOF MS) and gas chromatography (GC) combined with mass spectrometry(MS). A total of 43 different TAGs were characterized based on their Q-TOF MS accurate molecular weight and MS2 fragment ion profiles in the broccoli seed oil. There were 13 pairs of isomers in 43 TAGs. ELE， ELnE and GLnE were the three major TAGs. Among all TAGs， 15 TAGs contained erucin， contributing about 77.99% of the total TAGs. For the fatty acid compositions， erucic acid was the greatest fatty acid in broccoli seed oil， followed by oleic acid and linoleic acid. The chemical compositions of TAGs and fatty acids could promote the understanding about the chemical profiles of broccoli seed oil， thus improve the potential availabilities of developing function foods with broccoli seed oil in the future.