The topoisomerase II inhibitor etoposide causes an accumulation of DNA double strand breaks within the nuclei of cells. In this study, we investigated the effect of etoposide on the cell growth and apoptosis of human RPE cells. Etoposide evoked a significant inhibition of cell growth, and also induced DNA fragmentation in ARPE-19 cells. In addition, etoposide significantly up-regulated the expression of heme oxygenase-1 (HO-1), which is a stress-responsive protein and is known to play a protective role against the oxidative injury. And, etoposide-induced HO-1 expression was affected by the ROS scavenger N-acetyl cysteine. We also used oligonucleotides interfering with HO-1 mRNA (siRNA) for the inhibition of HO-1 expression. Interestingly, knock-down of the HO-1 gene significantly increased the level of DNA fragmentation in etoposide-treated ARPE-19 cells. In conclusion, these results suggest that up-regulated HO-1 plays as an anti-apoptotic factor in the process of apoptosis of ARPE-19 cells stimulated by etoposide.