Abstract: The effect of short term enalapril monotherapy （10～40 mg/day,4 weeks） on regression of left ventricular hypertrophy（LVH） in 24 patients with essential hypertension （EH） was studied and compared with 13 patients without LVH.The results showed that the LVMI and IVST decreased significantly along with lowering of the blood pressure.However,the LVMI and IVST increased significantly in patients without LVH despite of the similar decrease of blood pressure.