The main aim was to evaluate the measurement properties of the Family Needs Questionnaire-Revised (FNQ-R) in family members of individuals living with severe traumatic brain injury (TBI). A total of 309 family members of individuals with severe TBI from Colombia, Denmark, Mexico, Norway and Spain participated. Rasch analysis of the FNQ-R and its 6 subscales was conducted. The Rasch analysis indicated a lack of fit of the 37-item FNQ-R to one single underlying construct of needs, and less than half of the items were invariant across the countries. Misfit of single items was revealed in the Need for Health Information, Need for Emotional Support, Need for Instrumental Support, Need for Professional Support and Need for Community Support Network subscales. Fit to the Rasch model was obtained after removal of misfitting items. The Involvement in Care subscale had too few items to be adequately assessed by the Rasch approach. The FNQ-R is a well-targeted instrument for assessing the unmet needs of caregivers regarding the need for health information, emotional support, professional support and a community support network after some scoring adjustment and the removal of misfitting items. Caution should be taken when comparing responses across countries.