Whether high-normal blood pressure (BP) is a predictor of new-onset electrocardiographic (ECG)-left ventricular hypertrophy (LVH) is not known. A total of 4112 subjects who underwent physical examinations were enrolled in this study. BP was measured on entry. Standard 12-lead ECG was recorded at initial evaluation and 3 years later. BP categories were defined on the basis of the 2013 European Society of Hypertension/European Society of Cardiology guidelines. Of the 4112 subjects, 133 developed ECG-LVH 3 years later. Crude cumulative prevalence rates of new-onset ECG-LVH were 2.0% for the optimal BP group, 3.2% for the normal BP group, 5.1% for the high-normal BP group and 5.0% for the hypertension group. After adjustment for age, gender, body mass index, smoking, low-density lipoprotein cholesterol, log-transformed high-density lipoprotein cholesterol, log-transformed triglycerides, estimated glomerular filtration rate, haemoglobin A1c, haemoglobin, uric acid and antihypertensive medication use, compared with the optimal BP group, the odds ratios of new-onset ECG-LVH for the normal BP, high-normal BP and hypertension groups were 1.52 (95% confidence interval (CI): 0.93-2.49, P=0.094), 2.38 (95% CI: 1.40-4.03, P=0.001) and 2.44 (95% CI: 1.43-4.18, P=0.001), respectively. Even high-normal BP was significantly associated with the presence of new-onset ECG-LVH.