Background: Major concerns have arisen about the challenges facing China in providing sufficient care to its older population in light of rapid population ageing, changing family structure, and considerable rates of internal migration. At the family level, these societal changes may produce care uncertainty which may adversely influence the psychological wellbeing of older individuals. This paper applies social support and control theories to examine the relationship between perceived availability of future care and psychological wellbeing of older adults in China, and how this relationship is moderated by economic insufficiency, health vulnerability, and urban/rural context. Methods: Analyses are based on data from the China Health and Retirement Longitudinal Study, a multi-panel nationally representative household survey of the Chinese population aged 45 years and older. Data are taken from 2013 and 2011 waves of the study, with an initial sample size around 17,000, in which around 11,000-14,000 respondents are used for our final regression model. The score of depressive symptoms was measured in both waves with the Center for Epidemiologic Studies Depression Scale (CES-D10), and perceived availability of future care was measured in 2013 by asking respondents the question "Suppose that in the future, you need help with basic daily activities like eating or dressing, do you have relatives or friends (besides your spouse/partner) who would be willing and able to help you over a long period of time (yes/no)?" Results: Multivariate regression analysis revealed that uncertainty regarding future care support was associated with greater depressive symptoms even after controlling for factors confounded with care uncertainty such as family structure, socio-economic status, and a lagged measure of depression. Further, older adults without an anticipated source of care faced double jeopardy in their depressive symptoms if they also experienced functional limitations. Conclusions: Considering rapid aging of the Chinese population, anticipated increases in chronic disease burden, and possible attenuation of filial care, this analysis suggests that older adults in China may increasingly face health and social conditions detrimental to their mental health. Polices that remedy these concerns should be discussed, developed and implemented.