AIM: To understand the effects of benazepril in treating the diastolic function of the left ventricular in patients with hypertention and coronary heart diseases(CHD).　METHODS: Forty-five hypertension patients with the left ventricular diastolic dysfunction(LVDD) received benazepril 10-20 mg, po,qd, for 5 mo. On the basis of receiving nitrates 36 CHD patients with LVDD added to receive benazepril 5 mg, po, qd, for 5 mo. Before and after the therapy, the utmost speed of the peak value at the left ventricular early diastole stage (E peak), the utmost speed of the peak value at the left ventricular late diastolic stage (A peak), the E/A ratio and peak filling rate (PFR) were determined by color Doppler echocardiography. 　RESULTS: After the therapy, the E peak, the E/A ratio and PFR were up higher than before the therapy, meanwhile the A peak dropped lower, there were significant difference respectively (P<0.01). 　CONCLUSION: The LVDD can be improved distinctly if the patients with hypertension and CHD take benazepril for 5 mo or so.