Aim To investigate carotid atherosclerosis in patients with old myocardial infarction and related risk factors of cardiovascular disease. Methods The plaque index and carotid intima-media thickness (IMT) were detected by high-resolution ultrasound technique in 38 patients with old myocardial infarction and 32 matched healthy controls. Results The patients with old myocardial infarction had obviously abnormal plaque index (3.47 ± 1.26 vs 0.35 ± 0.86, p<0.01) and IMT (1.04± 0.17 mm vs 0.63±0.25 mm, p<0.01) compared with the healthy controls. The prevalence rates of atherosclerotic plaques were 84.21% (32/38) and 18.75% (6/32), there was significant difference between the two groups ( P< 0.01). Multiple regression analyses showed that IMT was closely associated with age, total cholesterol and the status of hypertension. Conclusions The patients with old myocardial infarction had abnormal plaque index and IMT, there was close relationship between carotid and atherosclerosis. Carotid ultrasounic examination could help to predict the presence of coronary artery disease.