Fisetin, a flavonoid widely present in natural plants, exhibits diverse pharmacological activities including antioxidant, anti-inflammatory, anti-apoptotic, and anti-aging effects. Its protective roles within the mammalian reproductive system have gained increasing attention in reproductive medicine and natural product research. This review provides a narrative overview of the regulatory and protective effects of Fisetin on both female and male reproductive systems, with a focus on gonadal function, the reproductive microenvironment, and endocrine regulation. Key molecular mechanisms, such as antioxidant, anti-inflammatory, and metabolic pathways, are discussed. Additionally, challenges related to low bioavailability and the translational potential in both clinical and agricultural settings are considered. By consolidating current knowledge, this review aims to provide a foundation for future research and the development of natural interventions for reproductive health.