PURPOSE: Children with acute lymphoblastic leukemia (ALL), the most common pediatric malignancy, have a 5-year survival rate of better than 80%. Long-term survivors of childhood ALL, however, carry an elevated risk of early mortality from cardiac events and stroke and a disproportionately high prevalence of dyslipidemia and obesity, presumably as an adverse effect of treatment. METHODS: As part of a clinical follow-up study of 70 young adult survivors of childhood ALL, we evaluated the degree to which this high-risk group differed in knowledge about symptoms of heart attack and stroke from that of a population-based comparison group frequency-matched by age, sex, and body mass index. Questions from the Behavioral Risk Factor Surveillance System were used to assess health knowledge. RESULTS: Survivors of ALL scored considerably worse on symptom knowledge than did their population counterparts. The strongest association was observed for chest pain as a symptom of heart attack: ALL survivors were 14-fold more likely than the comparison group to answer the question incorrectly. Seventy-seven percent of survivors failed to identify pain in the jaw, neck, or back as a heart attack symptom. CONCLUSIONS: These results indicate an important gap in knowledge and underscore the need for health education among survivors of childhood leukemia that includes information about symptoms of myocardial infarction and stroke.