Purpose: This study sought to compare the long-term outcomes of surgeries for retinal detachment (RD) secondary to viral or parasitic infectious retinitis. Methods: A total of 47 eyes that received pars plana vitrectomy with or without scleral buckling due to RD secondary to polymerase chain reaction-proven viral (cytomegalovirus, varicella zoster virus, and herpes zoster virus) or parasitic (toxoplasma and toxocara) retinitis from October 1, 2006, to June 30, 2023, in a single medical center were retrospectively enrolled. Results: Mean follow-up period was 59.03 ± 55.24 months in viral retinitis and 34.80 ± 33.78 months in parasitic retinitis after primary reattachment surgery. During follow-up, nine eyes (24.3%) with viral retinitis and five eyes (50.0%) with parasitic retinitis developed retinal redetachment. Visual acuity success at final follow-up was achieved in 19 eyes (51.4%) with viral retinitis and six eyes (60.0%) with parasitic retinitis (p = 0.64). The incidence of retinal redetachment during the 1st postoperative year was significantly higher in parasitic retinitis compared with viral retinitis (crude incidence, 0.21 vs. 0.85; p = 0.02). Hazard ratio analysis adjusted for age and sex showed 4.58-fold (95% confidence interval, 1.22–17.27; p = 0.03) increased risk of retinal redetachment in parasitic retinitis compared with viral retinitis during the 1st postoperative year. Tamponade with silicone oil and preoperative diagnostic vitrectomy were associated with significantly decreased risk of retinal redetachment in patients with parasitic retinitis. Conclusions Compared with RD secondary to viral retinitis, RD secondary to parasitic retinitis showed higher incidence of retinal redetachment during the 1st postoperative year. Tamponade with silicone oil and preoperative diagnostic vitrectomy were associated with significantly decreased risk of retinal redetachment in patients with parasitic retinitis.