To explore the syndrome of glucocorticoid-induced hypertension in the elderly, we analyzed the clinical findings from 35 patients aged more than 65 years (12 men, 23 women) who received glucocorticoid therapy. Resting blood pressures (BP) were less than 140/90 mm Hg before glucocorticoid therapy, and patients were apparently disease-free apart from the condition for which glucocorticoid therapy was prescribed. Glucocorticoid-induced hypertension is defined as systolic BP more than 160 mm Hg and/or diastolic BP more than 95 mm Hg after glucocorticoid administration. Glucocorticoid-induced hypertension was seen in 13 patients (37.1%); all patients with hypertension [steroid (glucocorticoid)-induced hypertension (SH(+)) group] received more than 20 mg of prednisolone daily, and BP rose rapidly within a week of commencing glucocorticoid administration. The SH(+) group did not differ significantly in terms of age, heart rate, blood count, plasma biochemistry, plasma renin activity, plasma aldosterone, routine urinalysis, or urinary electrolytes from patients who did not show hypertension [SH(-) group]. However, serum total calcium concentrations were significantly lower in the SH(+) group both before and after 2 weeks of glucocorticoid therapy than in the SH(-) group. Furthermore, the SH(+) group showed a significantly higher percentage of patients with a positive family history of essential hypertension than the SH(-) group. In conclusion, although the detailed mechanisms are as yet uncertain, glucocorticoid-induced hypertension occurs often in elderly patients, and is more common in patients with total serum calcium concentrations lower than the normal range, and/or in those with positive family history of essential hypertension.