Inclusion Criteria:  Females aged ≥ 18 years. Pathologic confirmed stage IIIC and IV epithelial ovarian cancer, fallopian tube cancer or primary peritoneal carcinoma Middle tumor burden and high tumor burden with cPCI score ≤ 12 based on pre-operative PET/CT examination Complete cytoreduction can be achieved based on PET/CT examination Patients must agree to undergo BRCA (breast cancer gene) and HRD (homologous recombination deficiency) testing Performance status (ECOG 0-2) Good ASA score (1/2)  Adequate bone marrow, renal and hepatic function to receive chemotherapy and subsequent surgery:  white blood cells >3,000/µL, absolute neutrophil count ≥1,500/µL, platelets ≥100,000/µL, hemoglobin ≥9 g/dL, serum creatinine <1.25 x upper normal limit (UNL) or creatinine clearance ≥60 mL/min according to Cockroft-Gault formula or to local lab measurement, serum bilirubin <1.25 x UNL, AST(SGOT) and ALT(SGPT) <2.5 x UNL. Comply with the study protocol and follow-up. Patients who have given their written informed consent.  Exclusion Criteria:  Non-epithelial ovarian malignancies and borderline tumors Low grade ovarian cancer Mucinous ovarian cancer Complete cytoreduction cannot be achieved according to preoperative evaluation, including pulmonary and hepatic parenchymal metastases, unresectable extensive pleural metastases, multiple thoracic lymph nodes metastases, brain or bone metastases Patient has a known hypersensitivity to the components of niraparib or its excipients Synchronous or metachronous (within 5 years) malignancy other than carcinoma in situ or breast carcinoma (without any signs of relapse or activity). Any other concurrent medical conditions contraindicating surgery or chemotherapy that could compromise the adherence to the protocol. Other conditions, such as religious, psychological and other factors, that could interfere with provision of informed consent, compliance to study procedures, or follow-up.