Objective: To study the chemical constituents of Mianyi composite decoction. Method: The constituents were separated and purified by column chromatography on silica gel

RP-silica gel and Sephadex LH20 from 30% alcohol elution on microporous resin chromatograph of Mianyi composite decoction. Their structures were elucidated on the basis of spectra data. Result: Eleven compounds were isolated and identified as 4-hydroxy-2(E)-nonenoic acid (1)

adenine (2)

quercetin (3)

luteolin (4)

adenosine (5)

scandosidemethyl ester (6)

astragaloside Ⅳ (7)

galloylpaeoniflorin (8)

propanoid acid (9)

salvianolic acid C (10)

apigenin-7-O-β-D-glucopyranoside (11). Conclusion: All of compounds were isolated from Mianyi composite decoction for the first time

and chemical type of compound 1 was isolated from single herb in Mianyi composite for the first time.