To investigate the relationship between the blood pressure control level and cardiovascular risk in type 2 diabetic patients, we evaluated home blood pressure, office blood pressure, biochemical data, and carotid echographic and echocardiographic findings in 148 patients with type 2 diabetes. According to the criteria for hypertension in the guidelines of the Japanese Society of Hypertension, we classified patients into a normotensive group with home systolic blood pressure in the morning (morning HSBP)<135 mmHg and office systolic blood pressure (OSBP)<140 mmHg, an office hypertension group with a morning HSBP<135 mmHg and OSBP>or=140 mmHg, an isolated home hypertension in the morning group with morning HSBP>or=135 mmHg and OSBP<140 mmHg, and a sustained hypertension group with morning HSBP>or=135 mmHg and OSBP>or=140 mmHg. In the isolated home hypertension in the morning group, the fasting insulin level, urinary albumin excretion, maximum carotid artery intima-media complex thickness, and left ventricular posterior wall thickness were significantly higher and the coefficient of variation for RR intervals was significantly lower than in the normotensive group. These results suggest that isolated home hypertension in the morning is a risk factor for target organ damage in type 2 diabetic patients.