Previous studies have found an increased prevalence of mixed/left handedness in male combat veterans and children with posttraumatic stress disorder (PTSD). This study examined lateral preference and screened for possible PTSD using a self-completion instrument in a general population sample (N = 596). Fifty-one individuals met all criteria for possible diagnosis of PTSD and, significantly, this group contained relatively more left handers; this effect was associated with strong left-handedness, rather than weak or mixed handedness. Left handers were found to have significantly higher scores in arousal symptoms of PTSD. This study extends previous findings to a civilian population and to women and suggests the association with left handedness may be a robust finding in people with PTSD.