Background: Dehydration in the older people is a prevalent problem that is often associated with physiological changes, physical limitations and environmental conditions., Objectives: The scoping review was carried out to identify risk factors associated with dehydration in older people living in nursing homes., Design: The revised scoping methodology framework of Arksey and O'Malley (2005) was applied. Study selection was carried out in accordance with Davis et al. (2009) and focused on the inclusion criteria (people over 65 years old and living in nursing homes). Risk factors were classified using the geriatric assessment., Data Sources: An electronic database search was performed in PubMed, Scopus and CINAHL. The literature search was carried out between October 2016 and January 2017., Review Methods: Thematic reporting was performed and study findings were validated through interdisciplinary meetings of experts. The quality of the papers consulted was also evaluated using the Newcastle-Ottawa Scale adapted for cross-sectional, cohort and case-control studies., Results: In all, 16 papers were analysed, all of which were observational studies. The risk of bias ranged from very low (n = 1), to medium (n = 13) and high (n = 2). The risk factors were classified in line with the different components of the geriatric assessment. In the socio-demographic characteristics age and gender were identified. In the clinical component, infections, renal and cardiovascular diseases and end-of-life situations were the most common factors highlighted in the papers analysed. With reference to the functional component, its limitation was associated with dehydration, while for factors of mental origin, it was related to dementia and behavioural disorders. Finally, the factors relating to the social component were institutionalisation, requiring a skilled level of care and it being winter., Conclusions: The most commonly repeated factors highlighted in the review were age, gender, infections, end of life and dementia, with it being important to highlight the large number of factors in the clinical component. Even so, the great majority of the factors were unmodifiable conditions associated typically associated with the physiology of ageing., (Copyright © 2018 Elsevier Ltd. All rights reserved.)