AIM:To study the preventive effect of Fufang Xueshuantong capsule on macular edema after phacoemulsification in diabetic cataract patients. METHODS: Using single-center randomized controlled clinical research,180 cases (180 eyes)of diabetic cataract patients were collected. Exclusion criteria included a history of previous intraocular surgery, vitreous loss during cataract surgery, uveitis, vitreoretinal pathology, glaucoma, cornea spot, and postoperative severe corneal edema, uveitis, anterior chamber bleeding, secondary glaucoma.They were divided into research group and control group. The research group patients （90 cases）had Fufang Xueshuantong capsule 1.5g tid immediately after surgery, continuously used for 2 weeks; the control group patients （90 cases） did not. The visual acuity of two groups and the incidence of macular edema were observed 1 day, 7 days, 1 month, 3, 6 and 12 months postoperatively. RESULTS:One day,7 days, 1 month, 3,6,12 months postoperatively, the mean vision of the research group was markedly higher than that in control group (P<001). In the research group, 12 cases had macular edema. 26 cases had macular edema in the control group. The incidence of macular edema in research group was markedly lower than that in control group（P<0.01）. CONCLUSION:After uneventful phacoemulsification in diabetic cataract patients,Fufang Xueshuantong capsule can improve the ischemia and hypoxia state of optic nerve and retina,reduce macular foveal capillary leakage and prevent the occurrence of macular edema.