Objective To investigate the relationship between the expression of vascular endothelial growth factor(VEGF)and the retinoblastome(RB)differentiation degree and the infitration capability. Method The VEGF expression in RB tissues of 40 cases was analysed by using LSAB immunohistochemical method. Results The VEGF expression in differentiated RB tissues of 13 cases was markedly lower than that in non-differentiaed RB tissues of 27 cases(P＜0.05);The VEGF expression in RB tissues of the optic nerve infiltrated group(14 cases) was significantly higher than of the optic nerve noninfiltrated group(26 cases)(P＜0.05)． Conclusion The results indicate that the VEGF expression is signficantly related with the differentiation degree and infiltration capability of RB. (Chin J Ocul Fundus Dis, 1999, 15: 238-240)