Since Hench successfully treated a patient with rheumatoid arthritis (RA) with glucocorticoid (GC) in 1948, the clinical usefulness of GC in the management of systemic autoimmune diseases has been established. However, serious adverse reactions of GC are the severe clinical problems. In addition, some of clinical evidences of GC therapy for these diseases are still controversial due to the difficulties for conducting clinical trials. In this review, we summarize the significance of GC therapy in autoimmune diseases such as RA and systemic lupus erythematosus, based upon the clinical reports for these diseases.