Ovarian cancer (OC) remains a leading cause of gynecological cancer mortality, driven by pronounced molecular heterogeneity, late diagnosis, and frequent acquisition of therapeutic resistance. The advent of CRISPR-Cas9 genome-editing technology has fundamentally transformed OC research by enabling precise, scalable, and unbiased interrogation of genetic drivers underlying tumor initiation, metastatic progression, drug resistance, and immune evasion. This review systematically summarizes the evolutionary trajectory of CRISPR-Cas9 platforms, from the discovery of the prokaryotic adaptive immune system to the development of high-fidelity nucleases, base editors, and prime editing systems. We then critically discuss the diversity of CRISPR-based library screening strategies, including CRISPR knockout (CRISPRko), CRISPR activation (CRISPRa), CRISPR interference (CRISPRi), and base editing libraries, highlighting their respective advantages, limitations, and technical considerations for high-throughput functional genomics. A major focus is placed on the broad applications of these tools in OC research, such as the systematic discovery of novel oncogenic drivers and metastatic mediators, the functional dissection of chemotherapy and PARP inhibitor resistance mechanisms, the construction of genetically defined patient-derived organoid and in vivo models, and the development of CRISPR-based diagnostic platforms for early detection and liquid biopsy monitoring. Furthermore, we provide an in-depth overview of emerging delivery systems for OC, including engineered viral vectors, non‑viral nanoparticles, physical methods, and exosome‑based platforms, with an emphasis on their adaptation to the unique peritoneal microenvironment. Finally, we highlight key translational challenges that currently constrain clinical implementation, such as off‑target editing risks, tumor heterogeneity, immune barriers, and ethical considerations, and propose future directions to overcome these hurdles. Collectively, the integration of CRISPR‑based functional screening with multi‑omics profiling, single‑cell technologies, and precision medicine frameworks offers a powerful paradigm for advancing personalized therapeutic strategies and improving long‑term outcomes for patients with ovarian cancer.
