Purpose: To investigate the spatial and temporal regulation effect of vascular endothelial growth factor(VEGF) on human fetal choroid vascularization.rnMethods: The eyeballs of 54 human fetuses from the 9th week to the 40th week due to accidental abortion were studied by immunohistochemically staining for the expression of VEGF and proliferation cell nuclear antigen (PCNA).rnResults: (1) The distribution of VEGF expression in the retinal pigment epithelium (RPE) decreased with the increase of age, the peak of which was between the 9th and 14th week. (2) PCNA immunoreactivity was localized within choriocapillaris endothelium. The expression level decreased alone with fetus age. In this period the choriocapillaris endothelium kept proliferation, differentiation, canalization and remodelled to form the choroid vessels. (3)Statistically significant correlations were shown between the expression of VEGF in the PRE and that of PCNA in choriocapillaris endothelium(r =0. 933, P ＜ 0. 01).rnConclusion: VEGF expression in RPE was positively involved in modulating human fetal choroid vascularization. Eye Science 2000; 16:11 ～ 14.