Protein-energy malnutrition is common amongst people aged 65 years and older, has a multifactorial aetiology, and numerous negative outcomes. Domiciliary carers (non-clinical paid carers) and family carers (including family, friends and neighbours) are required to support the increasing demand for in-home assistance with activities of daily living due to the ageing population. This review provides insight into the role of both domiciliary and family carers in providing individualised nutrition support for older, community-dwelling adults with malnutrition. Four electronic databases were searched for intervention studies from database inception to December 2016. Both domiciliary and family carers are well placed to monitor the dietary intake and nutritional status of older adults; to assist with many food-related tasks such as the sourcing and preparation of meals, and assisting with feeding when necessary; and to act as a conduit between the care recipient and formal nutrition professionals such as dietitians. There is moderate evidence to support the role of domiciliary carers in implementing nutrition screening and referral pathways, and emerging evidence suggests they may have a role in malnutrition interventions when supported by health professionals. Moderate evidence also supports the engagement of family carers as part of the nutrition care team for older adults with malnutrition. Interventions such as group education, skill-development workshops and telehealth demonstrate promise and have significantly improved outcomes in older adults with dementia. Further interventional and translational research is required to demonstrate the efficacy of engaging with domiciliary and family carers of older adults in the general community.