This article presents a population-based study of early childhood injury mortality following a nonfatal allegation of maltreatment. Findings are based on a unique data set constructed by establishing child-level linkages between vital birth records, administrative child protective services records, and vital death records. These linked data reflect over 4.3 million children born in California between 1999 and 2006 and provide a longitudinal record of maltreatment allegations and death. Of interest was whether children reported for nonfatal maltreatment subsequently faced a heightened risk of unintentional and intentional injury mortality during the first 5 years of life. Findings indicate that after adjusting for risk factors at birth, children with a prior allegation of maltreatment died from intentional injuries at a rate that was 5.9 times greater than unreported children (95% CI [4.39, 7.81]) and died from unintentional injuries at twice the rate of unreported children (95% CI [1.71, 2.36]). A prior allegation to CPS proved to be the strongest independent risk factor for injury mortality before the age of five.