Abstract: Soluble monosaccharides in ginkgo leaves were extracted by soaking in water heated at 60 ℃ in water bath for 2 h.The solution obtained was evaporated at 60 ℃ to dryness under reduced pressure.The residue was dissolved with dimethyl sulfoxide (DMSO),and derivatized with hexamethyldisilane (HMDS) and trimethylchlorosilane (TMCS) to form trimethylsilyl derivative.The capillary chromatographic column SE-30 (25 m×0.23 mm,0.1 μm) and FID were used in GC determination with inositol as internal standard.Seven monosaccharides were determined by the proposed method,with values of RSD′s (n=8) less than 10%.A comparative study of contents of monosaccharides in ginkgo leaves,with samples collected in spring and in autumn,as well as on samples taken from leaf-stalk,was made,giving results valuable for reference.