AIM:To investigate the effect of aescinate on the expression of NF-κB and the intervention to the rat cataract by ultraviolet(UV) rays. ·METHODS::The expression of NF-κB was detected by immunohistochemistry in different phase(3,12 and 24 hours)after the rat lens epithelial cells were cultivated in RPMI 1640 which were exposed to UV radiation. ·RESULTS:The expression of NF-κB in the UV groups was significantly higher and it was positively correlated with the degree of lens opacity. Compared with the different doses of aescinate groups and the UV radiation treatment group:the expression of NF-κB in the high dose group was lower than that of the mean,low dose and UV group(P<0.01),and there was no significant difference between the low-dose treatment and UV radiation group(P>0.05) and there was significant difference between the mean dose treatment and UV radiation groups(P<0.05).·CONCLUSION:UV can induce the activation of NF-κB. Aescinate can inhibit the activation of NF-κB expression and the occurrence of UV-induced cataract in the rat lens epithelial cells and has a dose-dependent effect.