A high performance liquid chromatography-tandem mass spectrometric（HPLC-MS/MS） method was developed for the analysis of the absorbed components in serum after intragastric administration（i.g.） of Xianlinggubao（XLGB）,a kind of traditional Chinese medicine prescription,to rats.Methanol-acetonitrile（2∶1） was used for serum sample pretreatment.The separation of components was achieved on a C18 column by gradient elution with acetonitrile（containing 0.1% formic acid）-0.1% formic acid water solution as mobile phase.The ion acquisition was performed by full scan MS and MS/MS in positive ion mode.The serum after i.g.XLGB to rats,blank serum of rats and XLGB were analyzed by HPLC-MS/MS.13 prototype compounds were confirmed and 2 metabolites were identified in serum by comparing the retention time and mass spectrometry fragmentation characteristics with that of reference substance added in blank serum as well as literatures,which mainly derived from Herba Epimedii Brevicornus,Fructus Psoraleae,Radix Dipsaci and Rhizoma Anemarrhenae.It revealed that these four compositive herb medicines contribute more to the effect of XLGB.The analysis of the absorbed components of Xianlinggubao in serum after administration would provide an experimental basis for revealing the in vivo bioactive components of Xianlinggubao in anti-osteoporosis.