Purpose: Masked hypertension (MH) has been drawing attention recently because this condition is often seen in untreated and treated individuals and is associated with target organ damage and a poor cardiovascular prognosis. Arterial stiffness is associated with organ damage in patients with primary hypertension. The aim of this study was to evaluate pulse wave velocity (PWV) in MH and true hypertension (TH). Methods: We enrolled 146 patients (mean age 47.9짹13.9 yrs, male 78 (53.4 %)), who was recently diagnosed as hypertension. MH was defined as office normotension (systolic blood pressure(SBP)<140mmHg or diastolic blood pressure(DBP)<90mmHg)and ambulatory hypertension (daytime average SBP���135mmHg or DBP���85mmHg), and TH was defined as office hypertension (SBP���140mmHg or DBP���90 mmHg) and ambulatory hypertension. We compared carotid-femoral, carotid-radial PWV and femoral-ankle PWV(cf/cr/faPWV), left ventricular mass index(LVMI) and left atrial volume index (LAVI) among normal control, MH and TH. Results: The MH group was the oldest. The crPWV, cfPWV and faPWV in TH and MH were significantly more increased compared it in normal control (p<0.0001). Also, the LVMI in MH was significantly higher compared to it in normal control (145.8짹35.8 mg vs 121.5짹14.5 mg, respectively)(p<0.05). Conclusions: The masked hypertension might be decreased arterial stiffness, which was similar to true hypertension. However, further larger study might be needed.