Rationale: Puerto Ricans have the highest prevalence of and morbidity from asthma of all ethnic groups in the U.S. One potential contributor to the high burden of asthma in Puerto Rican children is exposure to stress and violence. Objectives: To examine whether exposure to stress and violence is associated with an increased risk of asthma among Puerto Rican children. Methods: Population-based probability sample of children in the San Juan and Caguas metropolitan areas in Puerto Rico. Information was collected in a household survey of 1,213 children and their primary caretakers. Measurements and Main Results: The prevalence of lifetime physician-diagnosed asthma was 39.6%. In the year prior to the survey, 14% of children had witnessed an act of violence, 7% had been victims of violence, and 6% had been victims of physical or sexual abuse. Although stressful life events and exposure to neighborhood violence were not associated with asthma, a history of physical or sexual abuse was associated with approximately twice the odds of current asthma [OR 2.52, 95% CI, 1.27-5.00], healthcare use for asthma [OR 1.95, 95% CI, .96-3.96], and medication use for asthma [OR 2.35, 95% CI, 1.05-5.26]. Conclusions: Physical or sexual abuse is associated with high asthma morbidity among Puerto Rican children. To our knowledge, this is the first report of an association between childhood abuse and asthma. Our findings highlight the importance of screening for asthma among victims of childhood abuse, and to be aware of the possibility of physical or sexual abuse among children with asthma.