BackgroundTranscutaneous electrical acupoint stimulation (TEAS) may contribute to blood pressure (BP) control, but the evidence remains insufficient. Our objectives were to evaluate the impact of TEAS on hypertension and determine the optimal frequency. MethodsA total of 120 hypertensive patients were randomly allocated to the TEAS-2Hz group, TEAS-10Hz group, or usual care control group in a 1:1:1 ratio. All patients were advised to continue their usual antihypertensive regimen. Additionally, patients in the TEAS groups received TEAS therapy 3 times per week for 4 weeks, with a 4-week follow-up. ResultsThe primary outcome was the change in systolic BP (SBP) from baseline to week 4. Secondary outcomes included changes in diastolic BP (DBP), mean arterial pressure (MAP), heart rate (HR), heart rate variability (HRV), and 12-item health survey (SF-12) at different time points. Both TEAS groups showed reductions in SBP relative to control (TEAS-2Hz group vs. control, −4.70 mmHg [95 % CI, −7.00 to −2.40 mmHg]; P < 0.001; TEAS-10Hz group vs. control, −8.66 mmHg [95 % CI, −10.97 to −6.36 mmHg]; P < 0.001). TEAS-10Hz provided a significant decrease in SBP than TEAS-2Hz (-3.96 mmHg [95 % CI, −1.66 to −6.26 mmHg]; P< 0.001). TEAS groups also exhibited reductions in DBP, MAP, HR, LF/HF ratio(LF/HF), very low frequency (VLF), and normalized low frequency (LF norm), and an increase in normalized high frequency (HF norm) than control. No differences were observed among groups in low frequency (LF), high frequency (HF), total power (TP), very low frequency (VLF), and SF-12. ConclusionTEAS might be a promising adjunctive therapy for hypertension, and the recommended frequency is 10 Hz, which should be confirmed in larger trials.