The evidence for use of direct oral anticoagulants (DOACs) in the management of post-operative cardiac surgery atrial fibrillation is limited and mostly founded on clinical trials that excluded this patient population. We performed a systematic review and meta-analysis of clinical trials and observational studies to evaluate the hypothesis that DOACs are safe compared to warfarin for the anticoagulation of patients with post-operative cardiac surgery atrial fibrillation. We searched PubMed, EMBASE, Web of Science, clinicaltrials.gov, and the Cochrane Library for clinical trials and observational studies comparing DOAC with warfarin in patients ≥18 years old who had post-cardiac surgery atrial fibrillation. Primary outcomes included stroke, systemic embolization, bleeding, and mortality. We performed a random-effects meta-analysis of all outcomes. The meta-analysis for the primary outcomes showed significantly lower risk of stroke with DOAC use (6 studies, 7143 patients, RR 0.64; 95% CI 0.50–0.81, I2: 0.0%) compared to warfarin, a trend towards lower risk of systemic embolization (4 studies, 7289 patients, RR 0.64, 95% CI 0.41–1.01, I2: 31.99%) and similar risks of bleeding (14 studies, 10182 patients, RR 0.91; 95% CI 0.74–1.10, I2: 26.6%) and mortality (12 studies, 9843 patients, relative risk [RR] 1.01; 95% CI 0.74–1.37, I2: 26.5%). Current evidence suggests that DOACs, compared to warfarin, in the management of atrial fibrillation after cardiac surgery is associated with lower risk of stroke and a strong trend for lower risk of systemic embolization, and no evidence of increased risk for hospital readmission, bleeding and mortality.