Background : The non-dipper is known to be related to worse prognosis in a population study. But if it is independent of nocturnal blood pressure(BP) or nocturnal dipping itself is still controversial, especially in clinical situation. Methods : 712 subjects among 1916 subjects in KORABP data base underwent echocardiographic examination were analyzed. Daytime and nocturnal blood pressure were calculated using narrow fixed time interval method. Nocturnal dipping was defined as (daytime systolic BP(SBP) – nocturnal SBP)/daytime SBP. Non-dipper was defined as nocturnal dipping below 10 %. Echocardiographic LV mass were measured by ASE-leading to leading edges. LVH was defined as LVMI > 54 g/m^2.7. Results : Age was 56.1 짹 14.4. 50.9% was female. Blood pressures were higher in CBP than in ABP in systolic BP(SBP) and diastolic BP(DBP), respectively( 144.1 짹 21.5 / 88.5 짹 14.9 mmHg vs 136.6 짹 15.7 / 72.9 짹 10.3 mmHg, p < 0.0001). LV mass index(LVMI) were 102.7 짹 28.5 g/m² and 47.3 짹 14.3 g/m^2.7. Nocturnal dipping was 6.76 짹 8.43 mmHg and proportion of non-dipper was 63.8%. In multiple linear regression analysis including daytime SBP, nocturnal SBP, and nocturnal dipping in enter mode, nocturnal SBP ( 棺 = - 1.096, p = 0.049 ), daytime SBP (棺 = 0.992, p = 0.026 ), and nocturnal dipping ( 棺 = - 0.790, p = 0.021 ) were independent factor for LVMI. In multiple logistic regression analysis, nocturnal SBP(OR: 1.97), BMI(OR:2.12), and age(OR:2.81) were independent factors for LVH. Conclusion : This study showed that nocturnal dipping is independent of nocturnal SBP to predict LVMI and that nocturnal dipping or non-dipper is not independent of nocturnal SBP to predict LVH.