Background <p>Vascular remodeling (VR), such as arterial stiffness and atherosclerosis (AS), is general pathological characters in the progression of hypertension. It is urgent to develop therapeutic strategies for VR in the progression of hypertension. Songling Xuemaikang capsule (SXC), a Chinese patent medicine, has been preliminarily demonstrated the benefits of lowering blood pressure (BP) and associated hypertensive symptoms. We further investigate the efficacy of SXC in treating the early stages of stage 1 hypertension and the mechanism among SXC, BP and VR.</p> Methods <p>This study is designed as a prospective, multicenter, double-blinded, randomized controlled trial. One hundred eligible patients with stage 1 hypertension will be randomly allocated 1:1 into the SXC or placebo treatment for 12 weeks. All individuals were required to follow a healthy lifestyle checklist throughout the process. The primary endpoint is 24-hour ambulatory systolic BP. Secondary endpoints include brachial-ankle pulse wave velocity, skin capillary density, 24-h ambulatory diastolic BP, daytime and nighttime average BP, and other efficacy indicators. The gut microbiome-metabolome profile was analyzed to explore therapeutic mechanisms.</p> Conclusions <p>This study will determine the clinical efficacy of SXC on stage 1 hypertension and obtain the possible therapeutic mechanism of SXC on BP and VR, supporting the evidence for traditional Chinese medicine intervention in the development of hypertension.</p> Trial registration <p>The study was registered on ClinicalTrials.gov (no. NCT06093932) on October 23, 2023.</p>