Standard therapy for advanced ovary cancer is T-C chemotherapy (paclitaxel, carboplatin) after initial cytoreductive surgery. Intraperitoneal (i.p.) chemotherapy has been studied for several decades to improve the survival rate in ovarian cancer. The results of the Gynecologic Oncology Group (GOG) 172 trial comparing i.p. vs intravenous administration(i.v.) of cisplatin and paclitaxel chemotherapy were published in 2006. It showed a survival benefit in favor of the i.p. arm. The NCI (National Cancer Institute) and GOG have conducted a meta-analysis on the past seven phase III trials comparing i.p. vs i.v. that showed significant improvement in survival. NCI advised i.p. as the treatment of choice for patients with advanced ovarian cancer optimally operated. However, there are many problems that make it difficult to compare the complex regime of i.p. arms with the control arm, including the low completion rate of the i.p. and the fact that the control arm was not the present standard chemotherapy (T-C). Although it has a possibility to become the standard therapy for advanced ovarian cancer, the optimal i.p. regimen remains unclear. Clinical trials are needed to determine the optimal drug for i.p. and optimal number of i.p. administrator in order to improve the survival rate in patients with advanced ovarian cancer.