Abstract： Objective To evaluate the therapeutic effect of intravitreal injection with bevacizumab (Avastin) (IVB)combined with extra-panretinal photocoagulation (E-PRP) for high-risk proliferative diabetic retinopathy (PDR). Methods A total of 57 eyes of 53 patients with high-risk PDR underwent intravitreal injection combined with E-PRP. The examinations of vision acuity, intraoeular pressure, iris fluorescein angiography (IFA), fundus photos and fundus fluorescein angiography (FFA) were performed on all of the patients before and 1, 2, 3, and 6 months after the treatment; the results of the examinations before and after the treatment were compared and analyzed. The average follow up was 6 months. Results The mean visual acuity was (0. 143 ± 0. 072) before the treatment and (0. 218 ± 0. 128) 7 days after the tretment; the difference was significant (t= -7. 940, P<0.05). The mean visual acuity 1, 3, and 6 months after E-PRP (0. 228± 0. 138, 0. 223 ± 0. 125, 0. 220 ± 0. 134, respectively) differed much from that before IVB (P<0. 05), but not so much from that after IVB (P>0.05). The mean intraoeular pressure of 21 eyes which had the neovascularization of pupil margin and iris surface before and 7 days after IVB was (26. 632±2. 629) and (19. 316±3. 092) mm Hg (1 mm Hg=0. 133 kPa), respectively; the difference was significant (t=12. 838, P<0. 05) . The mean intraocular pressure 1, 3, and 6 months after E-PRP was (16. 947±2. 345), ( 16.474 ± 1.611 ), and (16. 421±4. 702 )mm Hg, respectively, which differed much from that before and after IVB (P<0. 05). Neovascularization on the disc and the retinae of 57 eyes were subsided partly, and a significant reduction or disappeared of the area of retinal neovascularization and the blood vessel leakage were observed 7 days after IVB. The neovascularization of pupil margin and iris surface of 21 eyes disappeared, and the IFA leakage decreased. The results of FFA 2 months after E-PRP showed that the one-off efficiency of E-PRP was 68.4%; 12 eyes (21.1%) needed an additional laser, in which 6 eyes (10.5 %) underwent vitreous surgery. Conclusion IVB combined with E-PRP as a treatment for high-risk PDR may improve the regression of retinal neovascularization and the reduction of vascular permeability, and prevent or reduce the complications and improve the therapeutic effect.