Nonimmune hydrops fetalis (NIHF) poses a significant challenge in perinatal care due to its high mortality rates and diverse etiologies. This comprehensive review examines the pathophysiology, etiology, antenatal diagnosis and management, postnatal care, and outcomes of NIHF. NIHF arises from numerous underlying pathologies, including genetic disorders, cardiovascular causes, and fetal infections, with advances in diagnostic techniques improving identification rates. Management strategies include termination of pregnancy for severe cases and fetal therapy for selected treatable etiologies, and neonatal care involves assessing and treating fluid collections and identifying underlying causes. Prognosis depends on factors such as gestational age at diagnosis and the extent of resuscitation needed, with challenges remaining in improving outcomes for affected infants.