Objective To investigate effects of morning blood pressure surge (MBPS) on cardiac remodeling and cardiovascular events in patients with essential hypertension.Methods Totally,386 patients with essential hypertension were recruited into the study,146 with MBPS and 240 without it based on their dynamic blood pressure monitoring.All the patients were monitored by 24-hour ambulatory blood pressure measurements,24-hour Holter electrocardiography and echocardiography for dynamic blood pressure,left ventricular mass index (LVMI),left atrial dimension (LAD),atrial and ventricular arrhythmias and ST depression,and so on.Results Compared with non-MBPS group,patients with MBPS had significantly higher incidence of left ventricular hypertrophy (LVH),enlargement of left atrial dimension,cardiac arrhythmias and myocardial ischemia detected,with LVMI [( 119 ±21 ) g/m2 vs.(93 ±12) g/m2,P＜0.01],LAD [(46±11) mmvs.(38±10) mm,P＜0.05],LVH (67.1% vs.30.4%,P ＜0.01 ),atrial premature beats (98.6% vs.84.2%,P ＜ 0.05 ),atrial tachycardia ( 54.1% vs.20.8%,P ＜ 0.01 ),atrial fibrillations ( 24.0% vs.0,P ＜ 0.0l ); ventricular premature beats and ventricular tachycardia ( 79.5% vs.57.9%,P ＜ 0.05,and 6.8% vs.2.5%,P ＜ 0.05 ),ST-segment depression (33.6% vs.13.8%,P ＜ 0.01 ),respectively.And,53.2 percent of cardiac arrhythmia and 57.6 percent of ST-segment depression occurred at six to eight o'clock in the morning.Blood pressure early in the morning and MBPS associated with ST-segment depression at the corresponding time ( P ＜ 0.05 ).Conclusions LVH is more significant,cardiac arrhythmias is severer and myocardial ischemia is more common in hypertensive patients with MBPS than that in those of non-MBPS.