A 79-year old man was referred to our hospital because of multiple tumors in the liver and refractory left exudative pleural effusion. The blood examinations revealed an increase in tumor markers, such as α-fetoprotein and PIVKA II, and typical findings on the computed tomography suggested the hepatocellular carcinoma (HCC). Meanwhile, we detected positivity for antinuclear antibody (ANA) and decreased complement in both his serum and pleural effusion. Furthermore, the ANA/IgG ratio was higher in pleural effusion than in serum. Accordingly, we ultimately diagnosed lupus pleuritis accompanied with HCC. We considered treatment of HCC followed by lupus pleuritis, but he refused any invasive therapy. We then initiated steroid treatment for only lupus pleuritis. As a result, his pleural effusion almost disappeared within one week. Lupus pleuritis is one of the manifestations in systemic lupus erythematosus (SLE) that is found primarily in young women. Therefore, presenting by an elderly man or with pleural effusion is a rare clinical event, and patients who are accompanied with HCC have seldom been reported. Since the clinical course in our case was atypical, it has the possibility of paraneoplastic pathogenesis.