Background. A common sequela of head injury is "frontal syndrome", consisting in characteristic neurobehavioral disturbances. However, there is no ecologically valid research tool that would clearly indicate the presence of this syndrome. The goal of this article is to evaluate the authorized the Polish version of the Frontal Behavioral Inventory (FBInv), used to differentiate fronto-temporal dementia (FTD) from other dementias. Material and methods. The research involved 95 patients treated at the centers represented by the authors, divided into 3 groups: CHI, consisting of 39 patients with traumatic frontal lobe injuries; FTD, consisting of 28 patients with fronto-temporal dementia; and a control group of persons with post-traumatic depression without injury to the frontal lobes. The results were based on data obtained from caregivers in 24 categories of patient behavior covered by the FBInv. Results. We found important differences in total scores between patients with frontal syndrome from groups CHI and FTD, as against patients with post-traumatic depression. There are also noticeable differences between patients in group FTD and group CHI in terms of scores on particular test items. Conclusions. The FBInv in the authorized Polish version is both sensitive and specific in measuring neurobehavioral disturbances occurring in patients with post-traumatic damage to the changes in the behavioral and personality of these patients with the passage of time since injury or onset should be the topic of further research.