BACKGROUND Orbital metastasis originating from hepatocellular carcinoma (HCC), particularly as an initial manifestation in patients without a known history of HCC, is rare. Few reports exist on the treatment of patients having HCC with orbital metastasis using targeted therapy or immunotherapy. CASE REPORT We report a case of advanced-stage HCC in a 65-year-old man who first presented with progressive, painless blurred vision and proptosis of the right eye for 2 weeks. The patient had no history of chronic liver disease or cancer. Computed tomography revealed an enhancing hyperdense extraconal mass in the right orbit; a biopsy revealed metastatic HCC. Abdominal CT, which was performed to investigate the primary cancer, revealed a 1.2×1.6-cm arterial-enhancing nodule with venous washout in hepatic segment 5, associated with liver cirrhosis. The patient's serum alpha-fetoprotein level was 70.27 ng/dL. Chest computed tomography revealed lung metastasis. Thus, first-line systemic therapy combining durvalumab and tremelimumab was initiated alongside palliative radiotherapy targeting the right orbit, which began 1 week after the first dose of dual immunotherapy. The patient had significant clinical improvement, reduced proptosis, and serum alpha-fetoprotein levels. CONCLUSIONS Although orbital metastasis is a rare manifestation of HCC, physicians should recognize and consider aggressive investigations for early diagnosis, especially in patients with existing risk factors for HCC. Dual immunotherapy with durvalumab and tremelimumab in combination with radiotherapy can be considered a potential treatment option for managing advanced HCC with orbital metastasis.