Objective: Although life stress and adversity have emerged as risk factors for mental health problems and cognitive impairment among older adults, prior studies on this topic have been cross-sectional and based on relatively homogeneous samples. To address these issues, we examined prospective associations between lifetime adversity and symptoms of depression, anxiety, and cognitive impairment in a nationally representative, longitudinal sample of older adults in the U.S. Method: We analyzed data from the Health and Retirement Study (1992-2016). The sample included 3,496 individuals (59.9% female), aged ≥64 years old (M _age=76.0 ±7.6 years). We used the individual-level panel data and ordinary least squares regressions to estimate associations between childhood and adulthood adversities and later-life depression, anxiety, and cognitive impairment. Results: Many participants experienced a significant early life (38%) or adulthood (79%) stressor. Second, experiencing a childhood adversity was associated with a 17.4% increased risk of experiencing an adulthood adversity. Finally, childhood and adulthood adversities both prospectively predicted more symptoms of late-life depression, anxiety, and cognitive impairment. Discussion: These findings are among the first to demonstrate prospective associations between lifetime adversity and symptoms of depression, anxiety, and cognitive impairment in older adults. Screening for lifetime stressors may thus help health care professionals and policymakers identify individuals who could benefit from interventions designed to reduce stress and enhance resilience.