Many studies have reported that carotid parameters measured by ultrasonography were predictors for stroke. The aim of this study was to investigate by cross-sectional study in elderly people having cardiovascular risk factors whether those carotid parameters are markers for atherothrombotic infarction (AI) and lacunar infarction (LI). Subjects of this study were 314 patients aged 65 years or older who had controlled cardiovascular risk factors and assessed carotid artery by ultrasonography. Subjects were categorized into control, AI and LI group. Clinical characteristics (biochemical analysis, body mass index, systolic/diastolic blood pressure, smoking habits, hypertension, diabetes mellitus and statin therapy) and carotid parameters (maximum intima-media thickness (Max-IMT), plaque score (PLQ-S) and Maximum pulsatility index (Max-PI)) were compared among three groups. PLQ-S, Max-PI, frequency of PLQ-S > or = 10mm and frequency of Max-PI > or = 2.0 in the AI group were significantly higher than in the control group. There were no significant differences between control and LI group concerning those carotid parameters. Multivariate logistic regression analysis showed that there were significant correlations between AI and PLQ-S > or = 10mm (odds ratio 2.980; P = 0.011), AI and Max-PI > or = 2.0 (odds ratio 2.458; P = 0.038), but there was no significant correlation between those carotid parameters and LI. This study suggests that in high risk elderly people, PLQ-S and PI are better markers for AI than IMT, but those carotid parameters have poor associations with LI.