Dengue fever is a significant public health concern in tropical and subtropical regions, including Bangladesh, where it poses a substantial burden on healthcare systems due to its high incidence and potential complications. To assess the association between dengue severity and liver function in patients admitted to a tertiary care hospital in Dhaka, Bangladesh. This observational study included 130 dengue patients admitted between July and December 2023. Demographic data, clinical symptoms, dengue severity classification, and liver function tests (ALT, AST) were recorded. Statistical analyses, including chi-square and Fisher’s exact tests, were performed to evaluate the association between dengue severity and hepatitis, with significance set at p < 0.05. The majority of patients were aged 21–30 years (40.0%) and 10–20 years (22.3%). Fever was present in all cases, with abdominal pain (46.2%), vomiting (47.7%), and diarrhea (44.6%) being common. Dengue with warning signs was the most frequent diagnosis (69.2%), followed by severe dengue (16.9%) and dengue without warning signs (13.8%). Elevated SGOT and SGPT levels were observed in 67.7% and 56.2% of patients, respectively. A significant association was found between dengue severity and elevated liver enzymes (p < 0.001). Dengue severity is strongly associated with elevated liver enzymes, suggesting a link between dengue infection and hepatitis. These findings highlight the importance of routine liver function monitoring in dengue patients for early detection and management of hepatic complications.