To investigate the effects of internal limiting membrane (ILM) peeling on retinal attachment after a single surgery, and on postoperative visual acuity (VA) at 6 months, in eyes with macula-off rhegmatogenous retinal detachment (RRD) complicated by proliferative vitreoretinopathy (PVR). Nationwide, multicenter retrospective cohort study. The Japan-RD Registry database was used for analysis of patients who had undergone vitrectomy for macula-off RRD complicated by PVR. Multivariate analysis was performed to detect prognostic factors for retinal attachment after a single surgery and for VA at 6 months postoperatively. Retinal attachment after a single surgery or VA at 6 months postoperatively was the objective variable; ILM peeling, preoperative VA, PVR grade, age, and intraocular pressure were explanatory variables. Eighty-nine eyes met the inclusion criteria; ILM peeling was performed in 25 eyes (28%). Preoperative VA was significantly associated with retinal attachment, but ILM peeling did not (odds ratios = 2.1 and 1.3, respectively; p = 0.009 and 0.67, respectively). Poor preoperative VA and younger patient age were significantly associated with poor postoperative VA, but ILM peeling was not (β-values = 0.37, -0.008, and 0.15, respectively; p < 0.001, p = 0.02, and p = 0.15, respectively. Preoperative VA was a risk factor associated with retinal attachment. Preoperative VA and patient age were risk factors associated with postoperative poor VA. In eyes with macula-off RRD complicated by PVR, ILM peeling did not have a clear beneficial effect on anatomical and functional outcomes, suggesting that it may be unnecessary for eyes with this condition.