Abstract: The retention times and negative mass spectra of intact glacosinolates extracted from the kale and tai tsai and the reference samples are measured by high peformance liquid chromatography-electrospray ionization tandem mass spectrometry(HPLC-ESI/MS n,n=1～2), respectively. The unknown chromatography peaks in eight species of glucosinolates were certified by the sqnare peaks to normalization. Negative quasimolecular ion mass spectra were observed. Daughter ions at m/z 75 and m/z 97 present in the spectra of all the GS investigated and its are - and - moieties, respectively. Ions R-(C=NOH)-S -, which provides side chain information, were also observed.