Abstract: The chromatographic behaviors of new antimalarial drugs artemisinine, dihydroartemisinine and its ethers, carboxylic esters, carbonates have been studied using reversed phase high performance liquid chromatography. These compounds and their epimers can be completely separated on the octadecylsilane bonded stationary phase GYT-C₁₈ under isocratic condition with methanol-water as eluant and semipreparative separation may also be carried out by a I. D. 10 mm column packed with the same packing material.In studying the relationship between the retention and hydrophobicity of the above mentioned compounds, it was observed that, the capacity ratio k' increases with increase of the substituent's hydrophobicity, and the correlation of the logarithm of capacity ratio k' with Hansch's hydrophobic substituent parameter was established. Futhermore, the linearity between log k' and chain-length of the alkyl substituent was also obtained.The effect of the solvent composition on the retention time has been studied. The value of log k' decreases linearly with increase of the concentration of methanol in eluent.