Previous studies have demonstrated the anticarcinogenic activity of pomegranate extracts and genistein in a series of human cancer cells. In the present study, the potential anticancer effects of pomegranate extracts and genistein on inhibition of cell proliferation and induction of apoptosis in human breast cancer cells was investigated. Human breast cancer cells (MCF-7) were cultured as monolayers in complete RPMI 1640 medium. The cells were cultured for 48 hours to allow growth and achieve about 80% confluence in 48-well culture plates, and then exposed to the agents for 24 hours in single and combination treatments. Post-treatment growth rate and apoptosis induction were assessed by the use of a series of bioassays-lactate dehydrogenase and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (inner salt) for viability and cytotoxicity; acridine orange-ethidium bromide and terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling assays for induction of apoptosis. Both pomegranate extracts and genistein had significant (dose- and time-dependent) cytotoxic and growth inhibition effects on MCF-7 cancer cells. Both growth inhibition and cytotoxicity were significantly higher (P < .01) in the combination treatments than in the single treatments with either agent. The data revealed that both drugs in single and in combination treatments induced apoptosis in MCF-7 cells. Apoptotic induction in the combination treatments was significantly higher (P < .01) than in single treatments. Both pomegranate extracts and genistein inhibit the growth of MCF-7 breast cancer cells through induction of apoptosis, with combination treatment being more efficacious than single treatments.