BACKGROUND: Family caregivers provide most of the emotional, physical, and logistical support for people living with Alzheimer's disease and related dementias (ADRD). As the caregiving role intensifies with advancing illness, family caregivers navigate the cognitive and functional decline of the care recipient. They also must reconcile the shift from a mutual relationship to one of a primary caregiving role. The unique nature of ADRD makes pre-death grief highly prevalent among family caregivers. Reminiscence therapy, which uses memory prompts to evoke meaningful past experiences, has shown promise in improving psychosocial outcomes for individuals with dementia. Its potential to benefit caregivers through strengthened emotional connections, shared meaning, and mutual engagement among the dyad, however, has been largely underexplored. Guided by the Interdependence Model of Communal Coping and the Micro-Sociological Theory of Adjustment to Loss, the current study aims to assess the feasibility and acceptability of Living Memory Home for Dementia Care Pairs (LMH-4-DCP), a reminiscence-based online intervention for family caregivers and their care-recipients. METHODS: This multisite pilot randomized controlled trial (RCT) will evaluate the feasibility, acceptability, and preliminary efficacy of LMH-4-DCP. Seventy ADRD family caregivers will be targeted for randomization to a 1:1 ratio to the intervention (n = 35) or attention control (n = 35) conditions and will participate for 2 weeks. Recruitment will be facilitated by the project's two study sites located in urban metropolitan areas of the USA. Primary feasibility outcomes include recruitment, retention, and completion rates, website usability (e.g., perceived usefulness and ease of use), and intervention satisfaction. Exploratory analyses will be conducted to assess the preliminary efficacy of LMH-4-DCP in reducing pre-death grief and improving relationship quality. Outcomes will be measured using validated questionnaires at baseline and 2-week follow-up, along with semi-structured interviews with LMH-4-DCP participants. DISCUSSION: This pilot trial will offer foundational evidence regarding the feasibility and acceptability of the LMH-4-DCP intervention. Study findings will guide intervention refinements and inform the design of a larger-scale, fully powered RCT to evaluate its efficacy in reducing pre-death grief and enhancing relationship quality among ADRD family caregivers. TRIAL REGISTRATION: Clinicaltrials.gov: NCT06225986, Registered: January 9, 2024, ClinicalTrials.gov; https://clinicaltrials.gov/study/NCT06225986?term=living memory home&rank=1.