INTRODUCTION: The global prevalence of heart failure continues to increase, particularly in ageing populations. Many older patients receiving home-based medical care have limited access to standard diagnostic tools, such as chest radiography and echocardiography, which can delay the detection of disease progression. AMI-SSS01, an artificial intelligence (AI)-based portable phonocardiography device, enables rapid and reproducible analysis of heart sounds, potentially allowing earlier identification of heart failure exacerbations in home-based medical settings. This trial aims to evaluate the feasibility and safety of implementing the AMI-SSS01 phonocardiography system in patients receiving home-based medical care. METHODS AND ANALYSIS: This two-arm, parallel-group, randomised controlled feasibility trial is being conducted at two primary care clinics affiliated with the Research Organisation for Education and Network in Primary Care-Based Research Network in Nagasaki, Japan. Participants aged ≥65 years with symptomatic heart failure receiving home-based medical care are eligible for study inclusion. Participants are randomised in a 1:1 ratio to either the intervention group, in which AI-assisted phonocardiography using the AMI-SSS01 device is performed during physician home visits, or the control group receiving conventional home-based medical care without phonocardiography. Feasibility outcomes include recruitment rate, overall data completeness and completion and protocol-concordant completion rates for phonocardiography examinations. Safety outcomes include adverse events related to device use. The registered primary clinical outcome, collected as an exploratory clinical outcome, is the time from randomisation to hospitalisation for heart failure or cardiovascular death during the 24-week follow-up period. The registered secondary clinical outcome is the number of heart failure exacerbation events. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Nagasaki University Hospital Clinical Research Ethics Committee (CRB24-028). The findings will be disseminated through peer-reviewed publications and scientific conferences. TRIAL REGISTRATION NUMBER: Japan Registry of Clinical Trials (jRCT1072240118).