Purpose: To determine the long-term outcome of patients operated with pars plana vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD) and to identify potential predictors for poor visual outcome. Methods: Prospective, observational 30-month study of patients operated for primary RRD with PPV. Examinations were performed preoperatively and after months 2, 6, and 30. Results: Eighty-four patients (84 eyes) were included and 73 (86.9%) participated at month 30. The macula was attached in 30 (35.7%) patients at primary operation. The majority of patients (n = 59, 80.8%) achieved a good final best corrected visual acuity (BCVA ≤0.3 logMAR, ≥0.5 Snellen) with a better outcome in patients with the macula attached than detached (0.02 vs. 0.17 logMAR, p = 0.007). Variables associated with poor visual outcome were baseline BCVA >0.3 logMAR (p = 0.03), female gender (p = 0.02), silicone oil (p = 0.03), and larger areas of retinal detachment (p = 0.01). In multivariable regression analysis, female gender (OR = 8.5 [95% CI 1.8–39.8]) was the strongest risk factor for poor visual outcome. Conclusion: The majority of patients operated for primary RRD achieved a reasonable long-term visual outcome. Notably, female gender was associated with poor visual outcome, indicating a need for closer follow-up.