Angiogenesis is important for tumour vascularisation and growth, and is therefore a promising target for cancer therapy. The present study reports inhibition of in vitro angiogenesis in human umbilical vein endothelial cells (HUVEC) as well as in rat aortic rings at physiological concentrations of lycopene, that is, 1-2 μmol/l. At a final concentration of 1·15 μmol/l, a significant reduction (P < 0·05) in network branching, that is, junction numbers, the number of tubules and tubule length, was observed in both HUVEC as well as in the rat aortic rings. The inhibitory effect of lycopene was independent of the presence of the pro-angiogenic agents, vascular endothelial growth factor and TNF-α. The anti-angiogenic effects of lycopene in the present study were shown at a concentration that should be achievable by dietary means. These results extend our knowledge of one of the putative anti-cancer actions of lycopene.