Background: The increase in life expectancy and age-related diseases, such as Alzheimer's disease, is a global challenge. Given the drawbacks of pharmacological treatments, it is important to pursue non-pharmacological strategies for dementia risk reduction. To effectively promote health and well-being in later life, multimodal, low-threshold, and cost-effective lifestyle interventions are needed. Methods: REMINDer is a monocentric, outcome assessor-blinded, randomized controlled pilot study to assess the feasibility and impact of a multimodal intervention delivered online (home-based and live-streamed). The 6-week (two one-hour sessions/week) online mind-body group intervention will be compared to a 6-week passive control (waitlist with delayed intervention) using a cross-over (AB-BA) design. The intervention was specifically designed for older adults and includes music, dance-based movement, and mindfulness. A total of N=50 cognitively unimpaired older adults will be enrolled and randomized into the two intervention arms using a block randomization with a 1:1 allocation ratio. Results: Outcomes will be assessed at pre-intervention, post-intervention, and follow-up using digital assessments of online questionnaires. Primary outcomes include feasibility, operationalized by adherence rates, and preliminary effectiveness of the intervention. The latter will be assessed by changes in self-reported mental and physical well-being, operationalized by the Short-Form Health Survey (SF-12). Secondary outcomes will include changes in self-reported health outcomes including cognitive, motor, sensory, emotional/affective, social, and lifestyle behaviors. Discussion: The study will provide evidence of the feasibility and preliminary effectiveness of an online multimodal mind-body intervention. If successful, the study may inform accessible lifestyle strategies to improve mental health and well-being and other risk factors for dementia in older adults. Registration:NCT06530277