A systematic review of the literature on mental disorder in prisoners, published in 2002, made no mention of post-traumatic stress disorder (PTSD), but indicators from other studies suggest that a history of serious and chronic trauma is common among offenders.To conduct a systematic review of the literature with the specific questions: does any epidemiological study of sentenced prisoners include data on prevalence of PTSD while in prison? If so, what is the prevalence in this group?Literature databases EMBASE, Medline, PsychInfo, PILOTS and SIGLE were searched. The Journal of Traumatic Stress was searched manually. Preliminary screening was conducted by reading abstracts of hundreds of papers. Ten exclusion criteria were then applied to the screened selection. Reference sections of all accessed papers were searched for any further studies.One hundred and three potentially relevant papers were identified after preliminary screening. Four met all criteria for inclusion and suffered none of the exclusion criteria. PTSD rates ranged from 4% of the sample to 21%. Women were disproportionately affected.All four papers suggested that the prevalence of PTSD among sentenced prisoners is higher than that in the general population, as reported elsewhere. Overall the findings suggest a likely need for PTSD treatment services for sentenced prisoners.