Osteonecrosis of the femoral head (ONFH) is a progressive disorder characterized by ischemia-induced death of the subchondral bone, most commonly affecting young and active individuals. More than one-third of patients have a history of corticosteroid use, while approximately 20% of cases are considered idiopathic. In the early stages, the disease may remain clinically asymptomatic; however, with progression, patients typically develop hip or groin pain accompanied by limitation of hip abduction and internal rotation. Treatment strategies are determined according to the stage of the disease and include conservative management, joint-preserving procedures, and salvage procedures. The aim of this review is to comprehensively summarize the etiology, pathophysiology, diagnostic methods, staging systems, and current treatment approaches for femoral head avascular necrosis.