Chronic hepatitis B (CHB) requires long-term antiviral therapy, but its broader effects on metabolic and cardiovascular outcomes remain underexplored. This nationwide retrospective cohort study aimed to evaluate the impact of antiviral therapy on dyslipidemia and major adverse cardiovascular events (MACE) in CHB patients. Using the Korean Health Insurance Review and Assessment database, we identified 441 191 patients, of whom 48 606 received antiviral treatment and were matched 1:1 with untreated controls by propensity score. Antiviral therapy was associated with significantly lower incidence rates of both dyslipidemia (14.63 vs. 18.20 per 100 000 person-years; IRR: 0.80, 95% CI: 0.76-0.85) and MACE (2.15 vs. 3.08 per 100 000 person-years; IRR: 0.78, 95% CI: 0.67-0.91). Tenofovir disoproxil fumarate (TDF) showed the strongest protective effects against both outcomes, with adjusted hazard ratios of 0.52 for dyslipidemia and 0.58 for MACE. Stratified analysis revealed that the protective effects of antiviral therapy against dyslipidemia and MACE were primarily observed in nondiabetic patients, while only a nonsignificant trend toward risk reduction was noted in diabetic patients. These findings suggest that antiviral therapy, particularly TDF, provides extrahepatic benefits, supporting its role in the long-term management of CHB beyond virologic suppression.