Objective To determinate the anthraquinones in plasma of patient with craniocerebral injuries after Rhubarb administration by the ultra-high performance liquid chromatography (UPLC).Methods MetChromatographic separation was performed on an Acquity UPLC BEH C18 column (2.1 mm x 100 mm, 1.7 μm) with methanol-0.5% aqueous acetic acid (12∶82) as mobile phase at a flow rate of 0.5 mL.min-1.The wavelength was set at 254 nm.The operating temperature was maintained at 25℃ and the sample volume injected was 5 μL.Linear range was satisfactory for determination of rhein in human plasma with the concentration range from 0.42 μg·mL-1 to 13.429 μg.mL-1.Four other anthraquinones were not detected with UPLC method.Results Recovery rate of this method was within the range of 97.2%-103.11%.The relative standard deviation of intra-and inter-day was less than 6%.The concentration of rhein in plasma after one hour administration from five TBI patients was 7.93±1.94 μg·mL-1.Conclusions The UPLC is a method with good precision, high recovery rate, simple operation, innocuity and good reproducibility.