The effect of the hexane extract of Curcuma zedoaria roots and its solvent fractions were investigated on the proliferation of SiHa, SNU-1 and HepG2 cell lines. Among those fractions, final fraction H2-3-1 and H2-3-3 showed cytotoxic effect on SiHa and HepG2 cell lines. The hallmark of apoptosis, DNA fragmentation, also appeared in the final fractions H2-3-1 and H2-3-3 after 24h treatment in SiHa cell line. Furthermore, those fractions were shown to be able to induce cell death in $[^3H]$thymidine incorporation test. These two fractions, H2-3-1 and H2-3-3 were determined as (-)-$alpha$-curcumene and $eta$-tumerone respectively by NMR and mass spectrum. From these results, it is speculated that te hexane extract of Curcuma zedoaria is necessary for further studies as a potent inhibitor of the growth of cancer cells.