Objective: To investigate accuracy of home blood pressure (BP) monitoring in the diagnosis of white-coat and masked hypertension in comparison with ambulatory BP monitoring. Methods: Participants were patients enrolled in the China Ambulatory and Home BP Registry, and underwent clinic, home, and 24 h ambulatory BP measurements. White-coat hypertension was defined as an elevated clinic systolic/diastolic BP (≥140/90 mmHg) and a normal 24 h ambulatory (<130/80 mmHg) or home systolic/diastolic BP (<135/85 mmHg), while masked hypertension as a normal clinic systolic/diastolic BP (<140/90 mmHg) and an elevated 24 h ambulatory (≥130/80 mmHg) or home systolic/diastolic BP (≥135/85 mmHg). Results: In untreated patients (n=200), the prevalence of white-coat hypertension (10.0% vs 17.0%), masked hypertension (26.5% vs 14.5%) significantly (P=0.04) differed between 24 h ambulatory and home BP monitoring. Regardless of the treatment status, compared with 24 h ambulatory BP, home BP measurement had low sensitivity (range 43%-86%) but high specificity (91%-99%), and accordingly low positive predictive values (46%-91%) but high negative predictive values (84%-100%). These two modalities had moderate diagnostic agreement (81%-90%) and Kappa statistic (0.43-0.78). Conclusion: Home BP monitoring has high specificitybut low sensitivity in the diagnosis of white-coat and masked hypertension. It may behave as a complementary to, albeit not a replacement of ambulatory BP monitoring.