Dose-dense early postoperative intraperitoneal chemotherapy (DD-EPIC) significantly increased non-progression rate in advanced ovarian cancer (OC) patients. We report final overall survival (OS) results to further strengthen the efficacy of DD-EPIC in the front-line therapy. In this phase 2 trial, 218 patients with FIGO IIIC-IV OC were randomly allocated to receive DD-EPIC followed by intravenous (IV) chemotherapy (DD-EPIC group), or IV chemotherapy alone (IV group). The study was prespecified to detect differences in progression-free survival (PFS) and OS. At a median follow-up period of 69.1 months, the median OS was 67.5 and 46.3 months in the DD-EPIC and IV group, respectively. The probability rate of OS at 5 years was 61.0% with DD-EPIC, and 38.2% with IV (hazard ratio [HR] for death from OC, 0.70; 95% confidence interval [CI], 0.49-1.00). DD-EPIC was associated with a prolonged PFS compared with the IV group (the estimated rate of PFS at 5 years, 26.0% vs. 8.5%; HR for disease progression, 0.64; 95% CI, 0.47-0.86). DD-EPIC was associated with a longer OS than IV chemotherapy alone. It may be considered as a valuable option of the front-line therapy for advanced ovarian cancer.Trial registration: ClinicalTrials.gov, NCT01669226 (date of registration: August 20, 2012).