Here we report a case of pancreatic cancer(PC)with peritoneal dissemination, underwent conversion surgery following chemotherapy for 2 years. A5 5-year-old woman was referred to our hospital for treatment of PC. Abdominal CT scan revealed 3.0 cm of a pancreatic head tumor with abutment of the portal vein and the hepatic artery, classified as borderline resectable. Staging laparoscopy(SL)showed positive peritoneal cytology(CY). Gemcitabine(Gem)plus S-1 therapy(GS) was performed. Ten months after initial GS, SL revealed the disseminated nodule and positive CY. The regimen was changed to Gem plus nab-paclitaxel therapy(Gem plus nab-PTX). Since right ovarian tumor was detected by CT scan 6 months after initial Gem plus nab-PTX, laparoscopic oophorectomy was performed. Histological findings showed positive CY and ovarian metastasis of PC. Afterward, Gem plus nab-PTX has been continued for 8 months. Since SL after 2 years from initial chemotherapy showed negative CY and no metastatic lesion, pancreaticoduodenectomy with portal vein resection was performed as conversion surgery. According to General Rules for the Study of Pancreatic Cancer the 7th edition by Japan Pancreas Society, histological findings showed ypT3, ypN0, R0, and Grade 1b of histological effect. The patient is alive without recurrence 6 months after the resection.