Objective: To evaluate a possible physiological mechanism underlying links between low childhood socioeconomic status (SES) and poor adult health by (a) testing whether childhood SES is prospectively related to cardiovascular responses to laboratory stress in adulthood, and (b) by determining whether psychological resources buffer cardiovascular reactivity and promote better recovery from stress. Method: Participants (n = 246; 55% Black; mean age = 32 years) were from a population-based sample of men in Pittsburgh, PA. Childhood SES was measured through the Hollingshead index (parental education and occupation) across 10 waves between the ages of 6 and 16. In adulthood, cardiovascular measures, including systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), and high-frequency heart rate variability (HF-HRV), were taken during and following standardized laboratory psychological stressors. Participants completed measures of optimism, purpose in life, self-esteem, positive affect, and self-mastery, which were combined into a psychological resource factor. Results: Lower childhood SES predicted higher HR and SBP at recovery, independent of age, race, body mass index, current smoking, task demand, and current SES. Psychological resources moderated the association between childhood SES and SBP. Lower childhood SES predicted SBP recovery only among men with fewer psychological resources. Conclusions: Psychological resources may buffer the relation between low childhood SES and cardiovascular recovery from stress. This buffering may improve adult health to the extent that cardiovascular recovery contributes to the risk of low childhood SES for subsequent disease.