Objective: Studies have revealed a phenomenon called skin-deep resilience, which develops in upwardly mobile African American youth. They perform well in school, maintain good mental health, and avoid legal problems. Despite outward indications of success, they also show evidence of worse health in biomarker studies. Here we extend this research, asking whether it manifests in differential susceptibility to upper respiratory infection, and if it emerges in European Americans as well. Methods: The sample included 514 adults in good health, as judged by physician examination and laboratory testing. Participants completed questionnaires about lifecourse socioeconomic conditions, conscientiousness, psychosocial adjustment, and lifestyle factors. They were subsequently inoculated with a rhinovirus that causes upper respiratory infection, and monitored in quarantine for 5 days the development of illness. Results: Consistent with past work, African Americans from disadvantaged backgrounds displayed indications of skin-deep resilience. To the extent these participants were high in conscientiousness, they fared better across multiple domains of psychosocial functioning, as reflected in educational attainment, symptoms of depression, and close relationship quality (p values = .01–.04). But analyses of these participants’ susceptibility to infection revealed the opposite pattern; higher conscientiousness was associated with a greater likelihood of becoming ill following inoculation (p value = .03). In European Americans, there was no evidence of skin-deep resilience; conscientiousness was associated with better psychosocial outcomes, but not infection risk. Conclusions: These observations suggest that resilience may be a double-edged sword for African Americans from disadvantaged backgrounds. The same characteristics associated with academic success and psychological adjustment forecast increased vulnerability to health problems.