OBJECTIVE To evaluate the incidence rates of cystoid macular edema (CME) and epiretinal membrane (ERM) formation after uncomplicated primary 23-G and 25-G retinal detachment (RD) repair and to identify risk factors associated with postoperative CME and ERM formation. METHODS This was a consecutive interventional case series of 587 eyes that underwent one RD repair with 23-G or 25-G pars plana vitrectomy (PPV) with scleral buckling. Epiretinal membrane and CME were confirmed by optical coherence tomography (OCT) and fluorescein angiography (FA). RESULTS A total of 587 eyes with a mean follow-up of 404 days had incidence rates of 35.1% for ERM and 15.2% for CME. The incidence of ERM after combined PPV and scleral buckling (48.4%) (n = 61) was greater (p<0.0001) compared to that after PPV alone (31.2%) (n = 144). CONCLUSIONS Epiretinal membrane and CME develop frequently after small-gauge RD repair. Pars plana vitrectomy combined with scleral buckling is associated with a higher incidence of ERM. Patients might benefit from increased use of OCT and FA to help rule out CME/ERM.