With the increasing life expectancy and ageing population, long-term care has become an urgent policy issue worldwide. The informal care provided by family members, particularly adult children, is a key aspect of long-term care. However, socioeconomic transformations have resulted in changing family and demographic structures and increased geographic mobility, reducing the capacity of families to provide informal care and meet the caregiving needs of older adults. For ageing families, care preparation can be an effective method for coping with eldercare challenges, and care preparation is attracting increasing attention from researchers. This study seeks to conduct a systematic review for studies on caregiving preparation by adult children that were retrieved from six databases, to synthesise the available evidence, and to identify knowledge gaps and opportunities for future investigations. The characteristics and main themes of eighteen reviewed articles were identified and analysed. This study discussed various conceptualisations of caregiving preparation by adult children, the prevalence of caregiving preparation, the factors related to caregiving preparation, and the related consequences. On the basis of the systematic review findings, several limitations of the literature and directions for future research were proposed to promote care preparedness and the well-being of ageing families.