OBJECTIVE:To investigate the cytotoxic effects of homoharringtonine(HHT) on HXO-RB44 cell line and the cell death form induced byHHT in vitro. METHODS:MTT assay was adopted to establish survival rate of the tumor cells. Agarose gel electrophores was chosen to detect the genomic DNA from the cells exposed to HHT. RESULTS:In the concentration from 10-9 to10-4 mol/L HHT powerfully inhibited the growth of the cells (P＜0.05). Regular genomic DNA fragmentation from the cells exposed to 10-6mol/L HHT for 48 hours was shown to be typical DNA ladder on agarose gelelectrophoresis. CONCLUSION :HHT can induce retinoblastoma (RB) programmed cell death (PCD),the effects of which has close correlation with incubated period and concentration of HHT.