1. Extracts of the leaves of Eurya emarginata markedly inhibited the growth of leukemia cells such as HL-60, KG-1, U937, K562, and Jurkat. 2. When HL-60 cells were treated with the extract, DNA fragmentation, morphological changes and sub-G1 hypodiploid cells were observed. The expressions of c-myc mRNA were also dramatically decreased. 3. Cornoside and Eutigoside were isolated from the leaves of Eurya emarginata. 4. Eutigoside induced apoptosis through down-regulation of Bcl-2 expression and activation of caspases.