Distribution behavior of ketoprofen enantiomers was examined in a two-phase system containing R, R-di-tartarates or S, S-di-tartarates. The influences of different alkyl chain of R, R-di-tartarates or S, S-di-tartarates, concentrations of R, R-di-tartarate, organic solvent and content of methanol on partition coefficient and separation factor were investigated, respectively. The experimental results show that R, R-di-tartarates studied all form more stable diastereomeric complexes with ketoprofen S-enantiomer than with R-enantiomer. The partition coefficients and enantioselectivity generally increase with the addition of length of alkyl chain of alcohol. The concentration of chiral selector and methanol also have bigger influences on enantioselectivity.