Objective:To observe the effects of Yiqi Huoxue Lishui Daxie Formula combined with western medicine on proliferative vitreoretinopathy in patients after reposition for retinal detachment. Methods60 patients after reposition for retinal detachment were randomly assigned into treatment group and control group, 30 patients in each group. Patients in the control group received tobramycin dexamethasone eye drops and compound tropicamide eye drops, while those in the treatment group received Yiqi Huoxue Lishui Daxie Formula on top of the treatment in the control group for 7 consecutive days after surgery. The treatment course was 21 days in both groups. The clinical efficacy was observed, and changes in the PVR score, electroretinogram and intraocular pressure were compared.  Results:①The effective rate was 53.3% and 26.7% at 7 days after surgery, 86.7% and 60.0% at 30 days after surgery, and 96.7% and 83.3% at 60 days after surgery in the treatment and control groups respectively. There were statistically significant differences in clinical efficacy between the groups at each time point of observation (P<0.05). ②The PVR score decreased significantly in each group at 30 and 60 days after surgery compared to that before surgery (P<0.05). It was significantly lower in the treatment group than in the control group at 30 and 60 days after surgery (P<0.05). ③The amplitude and latency of a and b waves on electroretinogram increased at 60 days after surgery compared to those before surgery in each group (P<0.05). There were statistically significant differences in the amplitude and latency of a and b waves between the groups at 60 days after surgery (P<0.05).  Conclusion:Yiqi Huoxue Lishui Daxie Formula shows satisfactory clinical efficacy in patients after reposition for retinal detachment, suppresses PVR progression and promotes recovery of visual function.