Introduction: Injury is the leading cause of mortality and morbidity in adolescents worldwide, and injury rates have been shown to be higher among youth with intellectual disability. Despite this, injury among adolescents with intellectual disability remains poorly investigated. This study aimed to identify characteristics associated with injury among adolescents with intellectual disability living in the community. Methods: A cohort of adolescents with intellectual disability living in southern Queensland, Australia was investigated prospectively between January 2006 and June 2010. Personal characteristics were collected via postal questionnaire. Injury information, including mechanism and location of injury, was extracted from general practitioner records. The association between demographic, social and clinical characteristics of participants and episodes of injury was investigated using negative binomial regression. Results: A total of 289 injuries were recorded from 432 participants over 1627.3 years of study-time. The overall annual injury incidence was 17.5 (95%CI 14.7, 20.9) per 100 person years. Presence of ADHD and less severe disability was associated with increased risk of injury. Down syndrome and reduced verbal communication capacity were associated with decreased risk of injury. Falls accounted for the highest single mechanism of injury (19.0%) with the majority (73.2%) of injuries involving either upper or lower limbs. Conclusions: ADHD is a co-morbidity that increases risk of injury among adolescents with intellectual disability. A critical component of injury prevention is avoidance of the great variety of environmental risk factors for injury relevant to this population.