This study aimed at investigating the incidence of placement breakdown in Flemish family foster care (Dutch speaking part of Belgium) for unaccompanied children (UC), and to explore the association of breakdown with foster child, foster family and case characteristics. Data regarding breakdown in family foster care for UC are scarce and non-existing for Flanders. Case files of 107 UC who were placed in family foster care were analyzed. After one year 19 placements (17.8%) had terminated: 13 placements broke down (12.2%) and 6 placements ended positively (5.6%). Conflicts between the foster parents and the UC, parenting problems, conflicts between the foster parents and the biological family of the UC, and running away of the UC were the causes of placement disruption. UC who experienced trauma in the host country were more at risk of breakdown, whilst social contacts with peers of the same culture and social contacts with Belgian peers were protective factors for placement disruption. Therefore, special attention should be given to UC who experience trauma in the host country. Furthermore, facilitating contacts with peers from the same culture and from the autochthonous community is of major importance.