Hypertension is the most considerable but treatable risk factor for cardiovascular disease. Although physicians prescribe multiple antihypertensive drugs and promote lifestyle modifications, the real-world blood pressure (BP) control rate remains poor. To improve BP target achievement, we developed a novel digital therapeutic-the HERB software system -to manage hypertension. Here, we performed a randomized pilot study to assess the safety and efficacy of the HERB system for hypertension. We recruited 146 patients with essential hypertension from March 2018 to March 2019. We allocated eligible patients to the intervention group (HERB system + standard lifestyle modification) or control group (standard lifestyle modification alone). The primary outcome was the mean change from baseline to 24 weeks in 24-hour systolic BP (SBP) measured by ambulatory blood pressure monitoring (ABPM). The baseline characteristics in each group were well balanced; the mean age was approx. 57 years, and 67% were male. In the primary end point at 24 weeks, HERB intervention did not lower the mean change of 24-hour SBP by ABPM compared with the controls (adjusted difference: -0.66 mmHg; p = .78). In an exploratory analysis focusing on antihypertensive drug-naïve patients aged <65, the effects of the HERB intervention were significantly greater than the control for reducing 24-hour SBP by ABPM at 16 weeks (adjusted difference: -7.6 mmHg; p = .013; and morning home SBP at 24 weeks (adjusted difference - 6.0 mmHg; p = .012). Thus, the HERB intervention did not achieve a primary efficacy end point. However, we observed that antihypertensive drug-naïve adult hypertensive patients aged <65 years could be a potential HERB system-effective target for further investigations of the efficacy of the system.