AbstractAimThis study aimed to elucidate the effects of laparoscopic liver resection (LLR) vs open liver resection (OLR) for major complications (Clavien‐Dindo classification grade ≥ IIIa) in obese individuals with hepatocellular carcinoma (HCC).MethodsThe clinical records of 339 and 733 patients who underwent LLR and OLR, respectively, for HCC between 2000 and 2019 were retrospectively reviewed. Body mass index (BMI) groups were classified according to the definitions of the World Health Organization: underweight group, BMI ≤ 18.4 kg/m2 (LLR vs OLR: 27 vs 47); normal weight, BMI 18.5‐24.9 kg/m2 (211 vs 483); overweight, BMI 25.0‐29.9 kg/m2 (85 vs 181); and obese, BMI ≥ 30.0 kg/m2 (16 vs 22). The effects of obesity on major complications after LLR and OLR were investigated.ResultsIn total, 18 (5.3%) and 127 (17.3%) patients presented with major complications after LLR and OLR, respectively. There was no significant difference in the incidence of major complications after OLR in the four BMI groups. However, a stepwise decrease in the incidence of major complications after LLR was observed from the underweight to the obese group. In addition, a multivariate analysis revealed that increased BMI was an independent preventive factor for major complications after LLR (P = .026, odds ratio: 0.84). The estimated adjusted risk of major postoperative complications decreased with increased BMI in the LLR group, while the risk did not decrease in the OLR group (P for interaction = .048).ConclusionLaparoscopic liver resection is beneficial for obese patients and is superior to OLR.