We aimed to assess parameters reflecting left ventricular function by dual-source computed tomography (DSCT) with echocardiography (ECG) as control. Fifty-eight patients with coronary heart disease (CHD) were recruited from January to June 2011; 29 CHD patients had type II diabetes. All patients were assessed by cardiac DSCT and ECG examination. DSCT and ECG correlated well for ejection fraction (EF) (r = 0.70), end-systolic volume (ESV) (r = 0.87), stroke volume (SV) (r = 0.83), and end-diastolic volume (EDV) (r = 0.90). The mean ESV and EDV values measured by the two methods in CHD patients with type II diabetes were higher than those in non-diabetic patients, whereas the mean EF was lower. DSCT is an accurate and practical method for assessing left ventricular function.