The anti-angiogenic property of vitamin E compounds, with particular emphasis on tocotrienol, has been investigated in vitro. Tocotrienol, but not tocopherol, inhibited both the proliferation and tube formation of bovine aortic endothelial cells, with delta-tocotrienol appearing the highest activity. Also, delta-tocotrienol reduced the vascular endothelial growth factor-stimulated tube formation by human umbilical vein endothelial cells. Our findings suggest that tocotrienol has potential use as a therapeutic dietary supplement for minimizing tumor angiogenesis.