2′,4′-Dihydroxychalcone (TFC), one of the main components in Herba Oxytropis, belongs to the flavonoid group, which is known to have anti-tumor activity in vitro. In this study, the authors examined the effects of TFC on cell proliferation and apoptosis in human gastric cancer MGC-803 cells. The MTT assay results showed that TFC was able to induce cytotoxicity in MGC-803 cells in a concentration- and time-dependent manner. Acridine orange/ethidium bromide (AO/EB) staining analysis indicated that the cytotoxicity induced by TFC was mediated by apoptosis, and flow cytometry analysis indicated an increase in apoptotic cells after treatment with TFC. Furthermore, typical apoptotic morphology such as condensed chromatin, irregular nuclei, vacuoles, and dispersed granular material in the nuclear compartment were also observed using a transmission electron microscope. These results suggested that TFC can inhibit the growth of MGC-803 cells and induce apoptosis. However, further studies are necessary to investigate the possible mechanism.