Background/Objectives: Coronary artery bypass graft (CABG) is associated with inflammation and complications, potentially leading to prolonged ICU and hospital stays. Omega-3 PUFA has anti-inflammatory properties, thought to potentially reduce complications in CABG patients. This study aims to systematically review and meta-analyze the impact of perioperative omega-3 PUFA supplementation on total ICU and total hospital stays in CABG patients; Methods: Randomized controlled trials examining the effects of omega-3 PUFA supplementation (IV/oral) on ICU and hospital stays in CABG patients were included. Studies were searched for in PubMed, EMBASE, PsychINFO, CINAHL, and the Cochrane Central Register of Controlled Trial databases, along with hand searching of reference lists. The quality and risk of bias of the included studies were evaluated by two independent reviewers using the revised Cochrane risk-of-bias tool. Meta-analysis was performed using fixed or random effects models according to the level of heterogeneity by mean difference with their 95% confidence intervals; Results: Twelve studies were included in the qualitative analysis and seven in the meta-analysis. Omega-3 PUFA was associated with a significant reduction in days of hospital stay (-0.58 (95% CI -1.13, -0.04)). Subgroup analysis showed that only oral omega-3 PUFA supplementation resulted in a statistically significant reduction in length of hospitalization after subgroup analysis with MD -0.6 (95% CI -1.17, -0.04); Conclusions: This study suggests that perioperative omega-3 PUFA supplementation may reduce the length of hospitalization in CABG patients, especially when administered orally. However, the findings should be interpreted cautiously due to the high level of heterogeneity.