Objective This study was designed to establish an experimental Choroidal neovascularization (CNV) model in BN rats, which could exhibit high reproducibility and to evaluate the expression of pigment epithelium-derived factor (PEDF). Methods 30 rats were received krypton laser. 1 days, 3 days, 7 days, 14days, 21 days and 28 days after photocoagulation, fundus fluorescein angiography (FFA) wAS performed. Total RNA were abstracted from retinal and choroidal tissue and the mRNA of PEDF was detected by RT-PCR.Results FFA showed flurescein leakage from 1 week to 4 weeks after photocoagulation. The mRNA of PEDF were in significantly difference during 4 weeks by RT-PCR.Conclusions Kryton laser photocoagulation can be successfully used to produced CNV experimental model in the BN rat. This study gave us a effective way to evaluate the mechanism of CNV by RT-PCR.