70 cases of oxygen free radical of seperated polymorphonuclear leukocyte(PMNL) of peripheral whole whool changes were detected in this study. Study objects including 20 cases of normal take-no-medicine control group,21 cases of coronary heart disease (CHD) patients(subdivided into 8 cases take Captopril,6 cases take Enalapril and 7 cases take-no medicine) and 29 cases of hypertensive heart disease(HHD) patients(subdivided into 12 cases take Captopril, 6 cases take Enalapril and 11 cases take-no medicine).The results showed that after taking Captopril and Enalapril,the PMNL chemiluminescence CL) peak value and intergral in CHD and HHD patients were significantly lower than that in patients take-no-medicine group;PMNL-CL parameters in CHD patients take Captopril and Enalapril, HHD patients take Captopril and Enalapril had no significant difference than that in normal control group; the PMNL-CL parameters in CHD patients take Captopril and Enalapril,HHD patients take Capropril and Enalapril had no significant difference.