Nontraumatic osteonecrosis of the femoral head (ONFH) usually affects young and middle-aged adults and frequently leads to femoral head collapse and subsequent arthritis of the hip. The incidence of the disease is increasing in accordance with the increased use of glucocorticoids for the adjuvant therapy of leukemia and other myelogenous diseases as well as the management of organ transplantation. This review provides up-to-date knowledge on the etiology and pathogenesis, natural history of ONFH, and it also describes Association Research Circulation Osseous (ARCO) classification criteria of glucocorticoids- and alcohol-associated ONFH, and the 2019 ARCO staging system.