INTRODUCTION: Obesity is commonly reported to be associated with hepatocellular carcinoma (HCC) along with higher risks of mortality. However, there is a significant research gap regarding the outcomes of hospitalization due to HCC among obese patients compared to those without obesity. This study compares the outcomes of hospitalization among those two groups. METHODS: A total of 50,845 patients admitted from 2016 to 2019 with a principal admission diagnosis of HCC were identified using the International Classification of Disease 10 (ICD-10) coding from the National Inpatient Sample (NIS) database. Patients with a body mass index (BMI) >30 were stratified into the obese cohort, and those with BMI ≤30 into the non-obese cohort as per the ICD-10 coding criteria for obesity based on BMI. The primary outcome of the study was mortality, whereas the length of stay, total hospitalization charges, acute kidney injury (AKI), sepsis, and shock were the secondary outcomes. We also compared additional complications such as ascites, portal hypertension, acute liver failure, disseminated intravascular coagulation (DIC), hepatic encephalopathy, and hepatorenal syndrome between the two groups. A multivariate regression model was used to estimate the effect of obesity on outcomes of hospitalization due to HCC. RESULTS: The obese cohort comprised 10.64% of the study population, whereas the non-obese cohort comprised 89.36% of the study population. Compared to the non-obese cohort, the obese cohort of patients with HCC were more likely to have a higher comorbidity index (CCI ≥4: 79.76% in the obese vs 71.17 % in the non-obese cohort). Obesity was found to be a protective factor for in-hospital mortality; that is, the odds of in-hospital mortality among the obese cohort was 0.713 times than that of the non-obese group of patients with HCC. The obese cohort had a higher mean length of stay (6.3 days vs 5.6 days; p value: <0.001) and total hospitalization charges (109,108$ vs 85,406$; p value: <0.001), which was further validated on multivariate analysis. The obese cohort had 1.26 times odds of developing AKI compared to the non-obese cohort (p value: 0.005). Sepsis, shock, and other complications such as acute liver failure, DIC, hepatic encephalopathy, hepatorenal syndrome, and portal hypertension were not significantly different between the two groups. CONCLUSION: Obesity was associated with reduced in-hospital mortality among patients with HCC. However, obese patients with HCC were found to have higher healthcare resource utilization in terms of length of stay and total hospitalization charge along with the development of AKI. Clinicians should be mindful of the potential longer length of stay and associated complications such as AKI while managing obese patients with HCC. Contrary to commonly held notions, obesity and its relation with in-hospital mortality reported in this study warrants further explorative research.