BACKGROUND AND OBJECTIVES: Prehypertension according to JNC7 is common and is associated with increased vascular mortality. The importance of management in high-normal blood pressure (BP) is underemphasized. SUBJECTS AND METHODS: We analyzed major adverse cardiac events (MACEs) in the Korea Acute Myocardial Infarction Registry in normal BP (group I) and high-normal BP (group II) patients. RESULTS: Among 14871 patients, 159 (61+/-12.3 years, 122 males) satisfied the study indication. Six-month and one-year clinical follow-up rate was 88.9% and 85.8%, respectively. Group I had 78 patients (60.9+/-12.4 years). Group II had 81 patients (61.6+/-12.5 years). Demographics of patients were not different between groups. Treatment strategy was not different. Initial Thrombolysis in Myocardial Infarction flow grade 0 was less frequent in group II (n=32, 47.1%) than in group I (n=16, 21.9%) (p=0.001). Successful intervention rate was not different between group II (93.8%) and group I (97.1%) (p=0.590). Six-month MACE occurred in 3 patients in group I (4.4%) and 10 in group II (15.6%) (p=0.031). Compared with normal BP, the odds ratio for patients with high-normal BP was 1.147 (p=0.045, 95% confidence interval 1.011-1.402) for 6-month MACE. CONCLUSION: Even though high-normal BP patients had a better baseline clinical status, the prognosis was poorer than patients with normal BP. Therapeutic BP target goal for the patients with acute myocardial infarction should be <140/90 mm Hg, which is recommended in JNC7.