Abstract Introduction: Social and economic conditions in childhood have been found to predict cognitive ability in midlife and old age in high-income countries. This study examines the long-term effect of childhood conditions on cognition among a nationally representative sample of older adults in a low- and middle-income country. Materials and Methods: Data were obtained from the 2014 to 2015 Indonesia Family Life Survey Wave 5 (6676 respondents, aged 50 years and older). Cognitive function was assessed based on total score on a series of tests adapted from the Telephone Interview for Cognitive Status. Retrospective information was collected on childhood poverty, with questions including whether respondents ever experienced hunger before age 15, whether basic facilities were available, and the number of books in the childhood home. We used linear regression to examine the association between childhood conditions and cognitive function in later life. Results: The findings show that the numbers of facilities and books available in childhood homes are substantially associated with cognition in later life after taking adulthood characteristics into account. Childhood hunger has no significant association with cognitive ability in later life. Belonging to an older birth cohort and living in a rural area were shown to have negative associations with cognitive ability in Indonesia. Conclusions: Our findings suggest that childhood poverty, birth cohort, and living in a rural area may contribute to cognitive aging in Indonesia. Policies and interventions that target childhood poverty in developing countries may also recognize the rural– urban divide in access to educational and other socioeconomic resources.