This study aims to investigate the safety and efficacy of combination therapy of Fluzoparib combined With Dalpiciclib for platinum-resistant recurrent ovarian cancer through a single-center, prospective, single-arm, phase II clinical trial, to improve the overall treatment level and prognosis of platinum-resistant ovarian cancer.

1. Overall Design: This trial is a single-center, prospective, single-arm, phase II clinical trial to evaluate the safety and efficacy of combination therapy of Fluzoparib combined With Dalpiciclib for platinum-resistant recurrent ovarian cancer.
2. Experimental observation indicators: 1) Main indicators: progression-free survival (PFS), 2) Other indicators: overall survival (OS), objective response rate (ORR), and adverse reactions.
3. Sample size calculation: The median PFS of platinum-resistant recurrent ovarian cancer patients is 3.8 months. In comparison, the experimental group is expected to have a median PFS of 7 months, with an alpha value of 0.05. Following up for 1 year and considering a 10% dropout rate, this study plans to include 30 platinum-resistant recurrent ovarian cancer patients.
4. Data Processing: Enter data and use SPSS statistical software for statistical analysis. Statistical analyst: Clinical Statistics Department of Fudan University Cancer Hospital. Mailing address: 270 Dong'an Road, Shanghai.

Inclusion Criteria:

1. Age≥18 years old;
2. Sign the informed consent form;
3. Histologically-confirmed epithelial ovarian or fallopian-tube cancer or primary peritoneal cancer.
4. Tumor recurrence or progression within 6 months after using platinum-based drugs;

Exclusion Criteria:

1. Any uncontrolled medical condition that may put the patient at high risk during treatment .
2. Receipt of any other investigational medicinal product within the last 30 days before randomization.
3. Patients with ovarian cancer excluded by pathological or clinical diagnosis;
4. Physical intolerance patients;
5. Patients who are unwilling to participate in the clinical trial.