Background <p>With China’s rapidly aging population, addressing the health management of mild cognitive impairment (MCI) in community settings has become crucial for dementia prevention. This study focuses on developing an integrated primary care intervention (IPC) within primary care system to support home-dwelling older adults with MCI and explore the underlying barriers based on the Consolidated Framework for Implementation Research (CFIR) to the implementation and further scale up of the IPC intervention.</p> Methods <p>This study employs a hybrid effectiveness-implementation research type II design. The randomized controlled trail will be conducted to evaluate the IPC intervention for older adults with MCI through primary care networks. The intervention group receiving 16-week family doctor contract services (including online cognitive training, enhanced health management, and usual care) and the control group receiving usual care only. Effectiveness will be measured through changes in participants’ cognitive function (primary outcome), self-efficacy and quality of life (secondary outcome), complemented by cost-effectiveness analysis. Implementation factors will be examined through the CFIR before and during the intervention process.</p> Discussion <p>This study is expected to demonstrate the effectiveness and implementation of the IPC intervention in managing older MCI adults within primary care setting. The implementation analysis will identify key factors for scaling up the intervention within China’s primary care system, including necessary policy adjustments and training requirements for primary care providers. The findings will provide both practical guidance for China’s dementia prevention strategies and contribute to global knowledge about implementing community-based cognitive health interventions in primary care settings.</p> Trial registration <p>Chinese Clinical Trial Registry ChiCTR2500099744. Registered 27 March 2025.</p>