Frontotemporal dementia (FTD)is a neurodegenerative disease with symptoms that differs from other dementias. Commonly early symptoms in FTD are changes in personality and behavior, which can be interpreted as psychiatric disease. The delay in FTD diagnos is contributes to the burden of family caregivers. Therefore, it is important to have more knowledge about the pre-diagnostic stage. In this qualitative interview study, we explored fourteen family caregiver's experiences of the pre-diagnostic stage of frontotemporal dementia (FTD). Our findings suggest that the family caregivers experienced the pre-diagnostic stage of FTD as changes in the interpersonal relationship with their loved one. These changes were often subtle and difficult for family caregivers to explain to others. The findings from our study illuminate the importance of medical staff paying attention when a next of kin is concerned about subtle changes in a loved one. The findings also illuminate that awareness of FTD should be raised.