Circumferential pulmonary vein isolation (CPVI) has a high recurrence rate in managing persistent atrial fibrillation (AF). While some studies suggest that augmenting CPVI with additional left atrial BOX ablation can diminish this recurrence rate among patients with persistent AF, this approach remains controversial. This meta-analysis assesses the safety and efficacy of adjunctive left atrial BOX ablation in treating persistent atrial fibrillation. We conducted a comprehensive literature search across China National Knowledge Infrastructure (CNKI), PubMed, Web of Science, and Cochrane Library, focusing on randomized controlled trials. The primary outcome was the recurrence rate of any atrial arrhythmias (AAs) within one-year post-treatment, with the secondary outcome being the frequency of adverse events related to the surgery. The combination of CPVI and left atrial BOX ablation did not lead to a significant reduction in the overall recurrence rate of atrial arrhythmias (risk ratios (RR) = 0.86, 95% confidence interval (CI) = 0.73-1.02, I2 = 35%). However, subgroup analyses revealed that this therapeutic approach significantly decreased the recurrence rates of all atrial arrhythmias (RR = 0.67, 95% CI = 0.49-0.92, I2 = 15%) and specifically atrial fibrillation (RR = 0.53, 95% CI = 0.37-0.77, I2 = 0%) in patients with a left atrial diameter ≤44 mm. Notably, there was no significant increase in the incidence of procedure-related adverse events (RR = 1.04, 95% CI = 0.56-1.94, I2 = 0%). However, the durations of both the ablation (mean difference (MD) = 19.77, 95% CI = 15.84-23.70, I2 = 0%) and the overall procedure (MD = 15.64, 95% CI = 6.99-24.29, I2 = 0%) were longer due to the additional ablation steps. In patients with smaller left atrial diameters, augmenting CPVI with left atrial BOX ablation significantly lowers the recurrence rates of atrial arrhythmias and atrial fibrillation without elevating surgical risk levels.