Delphinidin, an aglycone form of anthocyanins, was demonstrated to have anti-carcinogenic potential. The compound at $50;{mu}g/mL$ caused a significant increase of quinone reductase activity, an anti-carcinogenic marker enzyme, in mouse hepatoma cell lines (Hepa1c1c7 and BPRc1). Delphinidin enhanced the expression of other detoxifying or antioxidant enzymes including glutathione s-transferase, gamma-glutamylcysteine synthetase, heme oxygenase 1, and glutathione reductase. It suppressed the proliferation of murine hepatoma cells in a dose-dependent manner, with approximately $IC_{50}$ of $70;{mu}g/mL$. These results suggest that delphinidin might be useful for cancer prevention.