We examined the association between five types of childhood maltreatment and initiation of injection drug use among a cohort of high-risk youth in Vancouver, Canada. Among 560 participants, 230 (41.1%) had injected drugs previously. In multivariate logistic analyses, only physical abuse (adjusted odds ratio = 1.91, 95% confidence interval: 1.29-2.83) was associated with injection drug use. These findings highlight the impact of childhood physical abuse on subsequent initiation into injection drug use among high-risk youth.