AIM: To explore the effect of EDTA and poly-L-lysine hinge on the rabbit after cataract (PCO) in the prevention and treatment role. METHODS: Forty eyes of twenty New Zealand white rabbits were randomly divided into A,B,C and D groups.The operations of extracapsular transparent lens extraction were performed on rabbit eyes in each group. Group A, the control group, was irrigated only with balanced salt solution (BSS) during operation. Group B,C,D, the treatment groups, were irrigated with diluted BSS of 10mg/L EDTA, poly-L-lysine, and EDTA and poly-L-lysine hinge. The opacity in posterior lens capsule was observed by routine examination after operation. Two months later,the densities of lens epithelial cells ( LECs) in the four groups were calculated through hematoxylin and eosin (HE) staining. The proliferating cell nuclear antigen(PCNA) and their expression were identified through immunohistochemical staining,and the average optical density (gray value OD) of PCNA expression was detected with medical image analysis system. RESULTS: After HE staining, the posterior capsule LECs density in group B,D was less than that in group A,C, and group D less than group B, the statistical analysis were significantly different (P<0.01);statistical analysis was no significant difference between group A and C (P>0.05). For the average optical density (gray) measured, PCNA expression in group A and group C were strongly positive, group B was partially positive, positive expression in group D was still less than that in group B. Statistical analysis of group B,D and group A, group B and D were significant difference (P<0.01). Group A and group C were no significant difference (P>0.05). CONCLUSION: In rabbits in vivo, EDTA, poly-L-lysine and EDTA hinge all have functions of inhibiting the proliferation of rabbit LECs, preventing and delaying the formation of PCO. Group D is superior to group B on inhibition of LECs, LECs inhibition of group C is not obvious.