Abstract: Structure of Saccharides and their Mass Spectrometric AnalysisFang Yiwei(Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080,China) Received Abstract:In this paper,the research work on structure elucidation of saccharides including identification of stereoisomers of eleven monosaccharides,differentiation of six glucosides and six galactosides,and analysis of linkage positions and isomers of monosaccharide units in fourteen oligosaccharides by fast atom bombardment mass spectrometry(FABMS) in combination with the stereoselective derivatization with substituted boronic acid,RH(OH)2 are reported.The analysis method for methylation of sugers and identification of the components and linkage types by retention times of gas chromatograph and mass spectra are reported too.Keywords:structure of saccharides,stereoisomer,linkage position,chemical derivatization,mass spectrometry.