Keoladeo National Park (KNP), situated in Bharatpur, Rajasthan, is one of India’s most significant wetland ecosystems and an internationally important site for the conservation of resident and migratory fauna. The park is recognized as a UNESCO World Heritage Site and Ramsar wetland and occupies a strategic position along the Central Asian Flyway. Despite covering only 2,873 ha, it supports an exceptionally rich assemblage of birds, fishes, reptiles, mammals, butterflies, dragonflies and other aquatic organisms. This review-based study assesses the faunal biodiversity of KNP, with particular emphasis on globally threatened species and the ecological processes supporting them. Published literature, official conservation reports, UNESCO and IUCN documents, Wildlife Institute of India information and current species assessments were synthesized. The park supports approximately 375 recorded bird species, including numerous raptors and wetland-dependent species, while 58 fish species, 71 butterfly species and more than 30 dragonfly species have also been documented. Threatened fauna associated with the park include the Critically Endangered Siberian Crane, White-rumped Vulture, Indian Vulture and Red-headed Vulture, as well as Endangered species such as the Egyptian Vulture, Steppe Eagle, Pallas’s Fish Eagle, Indian Skimmer and Black-bellied Tern. Major conservation challenges include uncertain water availability, altered hydrology, invasive alien species, habitat succession, pollution risks, regional land-use change and broader threats along migratory routes. Conservation priorities should therefore integrate hydrological security, adaptive habitat management, invasive-species control, long-term population monitoring, satellite-wetland conservation and community participation. Keoladeo demonstrates that conserving a managed wetland requires ecosystem-scale interventions extending beyond protected-area boundaries.