ObjectiveTo detect the content of vascular endothelial growth factor（VEGF）in aqueous humour and in vitreous of patients with proliferative diabetic retinopathy（PDR）．MethodsEnzyme linked immunosorbent assay（ELISA）was used，which is one of the basic methods of protein quantitative analysis．ResultsThe VEGF levels in aqueous humour of PDR（mean level 398．6 pg/ml）were higher than those of the controls（mean level 106.5 pg/mlP＜0.05）．The VEGF levels in vitreous of the four PDR（mean level 1395.2 pg/ml)were higher than those in aqueous humour of the four PDR(P＜0.05，Primer t test）．The increased VEGF level in vitreous was positively correlated with the level in aqueous humour．In the normal group，the mean value of VEGF in the vitreous was 64.6 pg/ml．In comparison with that of 1140.4 pg/ml in the PDR group，there was a significant difference between the two groups （P＜0.05，Primer t test）．ConclusionVEGF might play an important role in the pathogenesis of neovascularization of PDR．