42 coronary heart disease (CHD) (21 with NIDDM) were studied with a noninvasive cardiovascular autonomic function tests Namely; 1. Heart rate response to valsalva manoeuvre; 2. Immediate HR response to standing; 3. BP response to standing; 4. BP response to sustained handgrip, on two groups; Group 1: 21 NIDDM with CHD; Group 2: 21 CHD. The results showed that the incidences of abnormal of 4 tests were: 28.6%, 42.9%, 19.0%, and 42.9% in Group 1 respectively, and all were 0% in Group 2. Significant difference (P < 0.05) was found between two groups. It suggested that cardiovascular autonomic function tests is useful in diagnosing autonomic neuropathy in NIDDM with CHD patients.