OBJECTIVE The study used a retrospective cohort design to establish long-term mortality rates and predictors of mortality for persons after moderate to severe traumatic brain injury (TBI). METHODS Consecutive records of persons with moderate to severe TBI who were discharged from a large rehabilitation hospital in Pittsburgh, Pennsylvania in the years 1974-1984, 1988 and 1989 were reviewed. RESULTS Six hundred and forty-two eligible individuals were identified and mortality was ascertained up to 24 years post injury. One hundred and twenty-eight of these individuals were found to be deceased. Poisson regression analyses revealed at least a 2-fold increased risk for mortality compared to the general population. Pre-injury characteristics and levels of disability at discharge from in-patient rehabilitation were among the strongest predictors of mortality. CONCLUSIONS These data constitute evidence for premature death in the post-acute TBI population following a moderate to severe head injury and are discussed in relation to other research in the area.