Diffuse malignant peritoneal mesothelioma (DMPM) is a rare disease. Although most patients eligible for surgery undergo cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy, the role of perioperative systemic chemotherapy still remains undefined. Here we report the case of a 52-year-old female patient with advanced sarcomatoid DMPM. After five cycles of systemic pemetrexed and cisplatin, along with two cycles of regional hyperthermia, tumor resection with histomorphological examination showed a complete pathological response. We therefore conclude that there is a subgroup of DMPM patients that might benefit from systemic neoadjuvant chemotherapy with pemetrexed and cisplatin.