Human serum contains various factors able to modulate neovascularisation in mouse cutaneous angiogenesis test (SIA, serum induced angiogenesis). Among them are two important growth factors: vascular endothelial growth factor (VEGF) and interleukin 18 (IL-18). In our previous study, each of them, in doses comparable to concentration in human serum, presented pro-angiogenic activity after intradermal introduction into mice skin. The aim of the present study was to evaluate total in vivo angiogenic activity as well as concentration of VEGF and IL-18 in sera collected from 60 healthy people of various age (20-86 years old), and to analyze whether some correlations exist between studied parameters and persons age. We have found negative correlation between age and in vivo activity of serum, negative correlation between age and VEGF concentration and positive correlation between age and IL-18 level.