Abstract: Five anthraquinones from Rhubarb were separated by high speed countercurrent chromatography. When two-phase solvent system composition was petroleum ether:ethyl acetate:methanol:water (8:2:8:1), emodin was obtained. Rhein and aloe emodin were separated when the proportion of solvents was 3:4:3:2, while chrysophanol and rheochrysidin were separated at the proportion of solvents 12:2:12:1. The purities of emodin, rhein, aloe emodin, chrysophanol and rheochrysidin are 98.81%, 99.15%, 98.51%, 98.89% and 98.16% respectively by HPLC.

Key words: high speed countercurrent chromatography, aloe emodin, rhein, emodin, chrysophanol, rheochrysidin, separation