An 84-year-old woman experienced epigastralgia with increasing serum protein induced by vitamin K absence or antagonists -II(PIVKA-II) levels, and she was referred to our hospital. The serum levels of tumor markers were elevated[ alpha -fetoprotein(AFP) 22,640 ng/mL, PIVKA-II 35,140 mAU/mL], and a mass lesion of 7 cm in diameter in the right lobe of the liver with portal vein tumor thrombus (PVTT) in the major trunk was detected by abdominal computed tomography (CT) scan. She was diagnosed with unresectable hepatocellular carcinoma (HCC) with PVTT, and sorafenib in combination with intermittent cisplatin(CDDP) hepatic arterial infusion chemotherapy(HAIC)was performed. After 3 courses of the therapy, the serum levels of tumor markers were decreased (AFP: 16,283 ng/mL, PIVKA-II: 2,924 mAU/mL), and the size of the tumor had also decreased to 2 cm in diameter. PVTT decreased from Vp4 to Vp3. We judged that it was resectable, and extended right hepatectomy and portal vein embolectomy was performed. Complete tumor necrosis was seen during pathologic inspection of PVTT. Although she presented with refractory pleural effusion and ascites after operation, she recovered and left our hospital on postoperative day 70. No recurrences have occurred during the 6 months after the operation. Sorafenib in combination with intermittent CDDP HAIC is considered to be an effective therapy for advanced HCC with PVTT in the major trunk.