Objective To establish in vivo and in vitro the characteristic chromatograms of Mongolian medicine compound formula-Shudage-4,and affiliate and identify in vitro chemical compositions of Shudage-4 and its compositions in vivo absorbed into blood.Methods Wistar rats were intragastrically given Shudage-4 and its different single medicinal,and then serum samples were prepared and determined by using high performance liquid chromatography (HPLC).The HPLC characteristic chromatograms of in vitro samples of Shudage-4 and its different single medicinal and Shudage-4 medicated serum were established and analyzed.The chemical compositions in vitro of Shudage-4 and its compositions in vivo absorbed into blood after taken by rats were compared,affiliated and identified.Results There were totally 64 peaks found after analyzing in vitro HPLC characteristic chromatograms of Shudage-4.There were 23 chemical compositions absorbed into blood,and 17 in vitro ones absorbed directly into blood and 6 speculated as new metabolites.These 23 chemical compositions were all derived from different were derived from Gaoliangjiang (Rhizoma Alpiniae Officinarum,Galangal Rhizome),peak 14,from Muxiang (Radix Aucklandiae,Common Aucklandia Root) and peak 13,from Shichangpu (Rhizoma Acori Tatarinowii,Grassleaf Sweetflag Rhizome).The peaks 15,20,21 and 22 were derived from Gaoliangjiang,Muxiang and Shichangpu,peaks 6,10,17,18 and 19,from Gaoliangjiang and Shichangpu,peaks 7 and 16,from Gaoliangjiang and Muxiang,peak 11,from Muxiang and Shichangpu,and peaks 4,5,8 and 12,from the whole formula of Shudage-4,from which 7 chemical compositions were identified.Conclusion The chemical compositions and metabolites in blood may be the active principles of Shudage-4 with direct effects in vitro,which are derived respectively from different single medicinal in Shudage-4.