Background ; The cardiovascular disease is major cause of morbidiry and mortality. For early preventive management, early detection of subclinical organ damage is a main concern. Noninvasive techniques have developed for assessing the change of vascular properties and organ( Heart and kidney ). We assessed which modalities does help to detect early target organ damage in younger workers. Methods : Peoples in a worksite were enrolled and checked ambulatory blood pressure. We divided into two groups, control group(n=50) and masked hypertension group(n=48). We examed clinical factors, pulse wave velocity(PWV), carotid intima-media thickness(IMT), echocardiography and microalbuminuria. Results ; A mean age of the two groups were not significant difference (32.4짹7.5 years vs 35.2짹7.5 years in masked hypertension group, p=0.074). The masked hypertension group had higher waist circumference(82.7짹7.8cm vs 75.6짹7.7cm), higher PWV (13.2짹1.5 m/s vs 12.5짹1.7 m/s p=0.026), thicker mean IMT (5.0짹0.6 mm vs 4.7짹0.8 mm p=0.036), more distensable carotid artery. There were no significant difference of microalbuminuria, Left ventricular mass index, Left atrial volume index, hsCRP between two groups. Multiple logistic regression analyses showed that baPWV but not mean IMT, waist circumference associated with masked hypertension (p=0.039).Conclusion ; The change of vascular properties in masked hypertensive patients was early detected by baPWV. The baPWV may be main modality for detecting early subclinical organ damage, especially in younger peoples.