Objective:To observe the changes of the thickness of reti nal nerve fiber layer (RNFL) of optic disc in rats with chronic glaucoma continuously dete cted by optic coherence tomography (OCT). Methods:A total of 48 Wist ar rats (24 males and 24 females) were randomly divided into 3 groups with 16 ra ts (32 eyes) in each group. The right eyes were the photocoagulation eyes and the left ones were as the control. Laser photocoagulation with the wavelength of 532 nm was perfo rmed on the trabecular network of the right eyes to induce the chronic middlelevel oc u lar hypertension. The changes of the intraocular pressure (IOP) were observed. O pticdisc linear scanning of OCT was performed 3, 6, and 9 weeks after IOP incr e ased, and the thickness of RNFL of optic disc was detected by the computer. Eight rats in each group were killed and retinal histology slic es were used to detect the thickness of RNFL. The flatmount s of retina from the right eyes of the other 8 rats in each group were stai ned by 1% toluidine blue. The density of retinal ganglion cells (RGC) was calcul ated and the results were compared and analyzed. Results:IOP o f the rats increas ed chronically and moderately after photocoagulation. IOP of the experimental ey e 3,6, and 9 weeks after photocoagulation was obviously higher than which of the control eyes, respectively （P＜0.001）. The results of OCT showed that the thickness of the RNFL of the experimental eyes was (67.39plusmn;5.91) mu;m, (53.4 2plusmn;5.64) mu;m，and (44.35plusmn;5.76) mu;m 3, 6, and 9 weeks after photocoagulation, and the corresponding thickness in the control eyes was（80.32plusmn;5.87）, （79.69plusmn;5.69）, and （80.78plusmn;5.84）mu;m, respectively. The thickness of the retinal fiber layer detecte d by histological method was （64.38plusmn;6.54）, （51.47plusmn;6.4）, and （42.10 plusmn;6.10）mu;m in the experimental eyes 3, 6, and 9 weeks after photocoagulation, and (76.23plusmn;6.78), (78.64plusmn;6.15), and (77.64plusmn;6.63) mu;m in the control eyes. Regression analysis of the thickness detected by the two methods was made, and the regression coefficients was 0.932（P＜0.001）.The differ ence of the ave rage density of RGC between the two groups was significant (P＜0.05）. Conclusi on:Glaucoma model in Wistar rats may successfully set up b y photocoagulating the trabecular meshwork. The thickness of retinal nerve fiber layer of the optic disc in rats with chronic glaucoma detected by OCT and obser ved by the light m icroscope is accordant. The changes of the thickness of RNFL in rats with chroni c glaucoma could be continuously detected by OCT to investigate the progress of the glaucomatic retinopathy in rat model.