The purpose of this study is to investigate the apoptotic effect of Phellodendri Cortex water extract (PCWE) on pancreatic cancer cells and to find out the regulating mechanisms. Human-derived pancreatic cancer cell line, MIA PaCa-2 cells were treated by PCWE with various concentrations and the cytotoxicity was determined by MTT assay. The activation of Annexin V, DNA fragmentation, cell cycle arrest and caspase activation were observed to investigate the role of PCWE in pancreatic cancer cells. Also, to find out the regulating mechanisms, we examined the ROS production. The treatment of PCWE induced the cell death in both concentration and time dependent manner. The treatment of PCWE also increased the expression of Annexin V, DNA fragmentation, cell cycle arrest, and cleavage of caspase, which means cell-death PCWE induced was apoptosis but not necrosis. The ROS production was increased by PCWE treatment and the blockade of ROS inhibited the PCWE-induced cell death. These results could suggest that PCWE induced apoptosis via ROS release in pancreatic cancer cell.