A detection method of blood plasma danshensu and salvianolic acid B of dissipating blood stasis botanical is disclosed. The method includes: (1) pretreating mammalian plasma sample: applying the plasma with medicine to small column of Waters Oasis HLB activated by methanol and water; after leaching and eluting, drying and enriching the eluent; after redissolving with mobile phase, measuring by UPLC/MS; (2) UPLC/MS measuring: UPLC condition: chromatographic column: Acquity UPLC BEH C18, 2.1′100 mm, mobile phase A: water-acetonitrile-formic acid 95:5:0.1 v/v/v, mobile phase B: acetonitrile-formic acid 100:0.1 v/v; MS condition: electric spraying ion source (ESI), detecting with negative ion mode, scanning at the range of m/z 150-800. The method can be used for pharmacokinetics study of danshensu and salvianolic acid B in dissipating blood stasis botanical.